Ensemble Darkhorse

"in every masterpiece there are supporting characters who outshine the protagonist."

- Neito Monoma

The term "Dark Horse" has its origin in horse racing. A relatively unknown horse would be risky to place bets on, compared to a horse with a known track record, because the gamblers would be "in the dark," so when an unknown horse won a race it was called a "Dark Horse Victory." The term is also used in politics to describe a lesser known candidate who does better than expected in an election.

Generally, it's used to describe a side character making up part of the Ensemble, either a non-lead secondary character or a mere Flat Character, who can sometimes become unexpectedly popular with the fandom (sometimes, even more than the lead characters) depending on who and where the Fandom is, as well as what the other characters are like in comparison (for example, the hero is not as popular because s/he is too much The Everyman).

The writers or producers may be tempted to Retool the show's premise to put them in the spotlight. Sometimes this works, but usually it's a bad idea for two reasons, both relating to what happens when you take a supporting character and move him or her into the protagonist's position. The first is that writers often "adjust" the character so that s/he can fit into a conventionally heroic role—in the process destroying the unconventional traits that made the character an Ensemble Darkhorse in the first place. The second is that if the writers don't do this, traits that were entertaining in a secondary character may become grating and unpleasant in The Protagonist.

However, it's still good business to bring Darkhorse characters back, even if they were originally meant to be featured for only a short time. Thus, episodes which do not specifically require a certain character will be more likely to use the Ensemble Darkhorse.

Occasionally, if an antagonist becomes a Darkhorse, the writer may decide to have him perform a Heel Face Turn in situations where the only other option is being killed by the protagonists. However, if the series doesn't have an end planned, it's more likely that he'll just escape.

If the Ensemble Darkhorse becomes an important character, they're now a Breakout Character. See also Adaptational Badass, Ascended Extra, Memetic Bystander, Lower Deck Episode, A Day in the Limelight, and One-Scene Wonder. Creator's Pet is the polar opposite, a character who the writer grows fond of but the fans do not. An antagonist who becomes popular despite the author's intentions is Draco in Leather Pants—an example of Misaimed Fandom. The natural extension of this is the Spotlight-Stealing Squad.

Fan Works

 * Yawning Squirtle and Boulder-Dropping Whale in Sonichu, and Mary Lee Walsh, who is frequently the protagonist in various fanworks, and is drawn deliberately with a different design. This is mainly because many find that her real-life basis is actually pretty awesome. Plus, it ticks CWC off.
 * Bill the Scientist also qualifies for this, since he's also one of the Moon Pals.
 * Most Metal Gear fans who've seen Metal Gear Solid: Philanthropy report little interest in Solid Snake's mildly Out of Character behaviour, but absolutely love Pierre Leclerc. He has a decent-sized Estrogen Brigade, is popular with Journal Roleplay, and gets fanfic written about him.
 * Brother-Captain Allen of Tiberium Wars - stoic, calm, quiet, efficient, scary, and perfectly willing to Its no surprise that such a bit character has become so liked.
 * Harry Potter and the Guardian's Light gives us THE INDOMITABLE ARGUS FILCH. In the novels, he's a slightly scary background character. In the movies, he ranges from creepy to disgusting or comic relief. But in this fanfic, his first scene involves him arming himself alongside to go into the black forest and fight an army of trolls. Turns out, while he's not a janitor he turns a profit selling enchanted weapons. After he helps demolish the trolls with ease, we next see him tracking Harry down in his invisibility cloak despite not knowing it's Harry, or that he's in an invisibility cloak. Recently,  and Filch was first on scene. His response was to ask them for a hall pass. He then ducked around a corner and they traded some fire. He was ordered  to surrender. His response to that was to blow a troll's brains out, and say; "Alright, I surrender, now come a little closer!" It's easy to see why Dumbledore trusts this man to clean his school's floors.
 * Dragonball Z Abridged has Nappa. In the actual series he was a bland Giant Mook that was killed relatively expediently, but in Abridged he is quite possibly the funniest character in the series, and the fans loved him for it, to the point where . What's particularly funny is that Abridged!Nappa seems to be at least partially responsible for the actual Nappa becoming more popular over the years, with fans starting to appreciate him more thanks to TFS affiliate MasakoX's "What if Nappa Turned Good" series pointing out the surprising amount of potential he had as a character, among other things.
 * There is also popularity upon Super Kami Guru, Nail, Dodoria, Zarbon and The Ginyu Force (Specifically Recoome - these guys even got their own opening between Episodes 19 and 23.).
 * The moment Rocky and Adam stepped foot into Of Love and Bunnies, the story became almost as much about them as it did the Mighty Morphin Power Rangers and Power Rangers Dino Thunder.
 * Warriors the Abridged Series (the abriged series of Warrior Cats, not something else), the most popular characters are Bluestar, Redtail, Matthias and Rainstorm. Redtail and Matthias ech only appear in one scene.
 * While she was included mainly to intentionally avert the Ron the Death Eater treatment the character often gets, Ember in The Legend of Spyro: A New Dawn has been very well recieved by readers for being a kindhearted, friendly version of the character. This is part of the reason she ended up having a Day in The Limelight chapter were she This also enabled the writer to give her more character growth and an excuse to Take a Level In Badass, so it worked out in more ways than one.
 * Edfred in Naruto Veangance Revelaitons, who stands up to God Mode and Jerk Sue main character Ronan when he causes trouble in his store, making it clear he doesn't like him.
 * Brian Hahnel and Joan's dad (named Hugo by those on Twilight Sucks) were originally minor characters in Brewdening Love, a Twilight fanfic. Then the TS snarkers started shipping them, and the rest is history.
 * This Troper has inadvertently created his own Ensemble Darkhorse within his own fan fiction. In the story Memories, a minor character is introduced, the AI Cassandra, as little more than s ide character and plot device. Now, before the story has even been finished, this troper has accidentally developed the story to revolve around Cassandra's descent into rampancy, and is already planning further supplementary material based on the character and the consequences of her actions...
 * Then there's Pauline from the Tamers Forever Series Want to know how popular she is? There are Takari Fan Girls who ship Pauline and Takeru together. seriously
 * Three background ponies from My Little Pony: Friendship Is Magic - Lightning Bolt, Cloud Kicker and Medley - had little screen time and almost no lines in the show. In Ace Combat: The Equestrian War, they are a part of a heroic squadron and become a Communications Officer, Plucky Girl and Little Miss Badass respectively.
 * Friendship Is Witchcraft gives us Sweetie Bot, who has become one of the most recognizable characters and even has her own Tumblr.

Music

 * When The Beach Boys' Brian Wilson suffered an emotional breakdown in 1965 and decided to quit touring with the group, Bruce Johnston (previously of Beach Boys soundalike group the Rip Chords) was hired to take over his role playing bass onstage. By the end of the year Johnston was joining the Beach Boys in the studio and later became an integral part of their late '60s/early '70s recordings, even writing songs like "Disney Girls" for them.
 * Moreso Dennis Wilson, who went from being the under-appreciated drummer to writing such classics as "Forever", to the point that his solo album, "Pacific Ocean Blue", charted higher and was more critically acclaimed than the Beach Boys album released that same year.
 * The Beatles produced two possibilities:
 * Ringo Starr was a late replacement into the band and widely considered (however fairly) to be their least talented member. Furthermore, he was the least conventionally handsome of the group and, as the drummer, held the least glamorous position in the band. Despite all this, his goofy charm and approachable good looks earned him the most fan mail of any Beatle.
 * George Harrison was arguably the least popular Beatle during the band's run. He was not a part of the singing/songwriting superduo of Lennon-McCartney, nor did he have the charm of Ringo and was known for being quiet and moody. However, immediately after the band broke up he was the first of the four to score a #1 hit, and his album All Things Must Pass is to this day the top selling album by any solo Beatle. His ballad "Something" is also the second most frequently covered Beatles song after "Yesterday," and even John Lennon once remarked, "It's the best damn song on the whole album." Harrison seems to have been well aware of his dark horse status. He had a minor hit with the song "Dark Horse," and his custom record label was called Dark Horse Records.
 * Bone Thugs-n-Harmony is a group example. As they emerged during a era of hip-hop where you had to be either from the west or the east to make it in that particular field. Not only did they not hail from either coast, but hailed from the Midwest (Cleveland to be precise), and managed to have 3 back to back multi platinum records amidst the hype and controversy of the then bi-coastal feud between the east and west.
 * Despite being the bassist of Fall Out Boy as opposed to the frontman, Pete Wentz is arguably somewhat of a teen idol, dramatically more popular than the band's lead vocalist/rhythm guitarist Patrick Stump. His massively prominent fandumb is a common conversation topic among Fall Out Boy fans and music spectators. Wentz's scandalous notoriety is lampshaded in the music video for "This Ain't a Scene, It's an Arms Race" from Infinity on High.
 * Well, Wentz was basically the "head" of the band all throughout their run. Stump, despite being lead vocalist, was actually NOT the frontman of FOB until around Infinity on High and Folie a Deux came out. Then they broke up...
 * And Patrick went off to do his own solo thing, which has a mix of genres; Pete did Black Cards, a ska/pop/something; and Andy and Joe, in a completely off-the-wall and against type (not even Patrick's Prince-esque songs could compete) action, formed The Damned Things, a heavy metal band. Every person's fandom rejoiced.
 * Similarly, Aaron Gillespie, drummer/secondary vocalist of Underoath, is decidedly more popular among the young females of the band's fanbase than frontman Spencer Chamberlain, due to his angelically emotive vocals (in contrast to Chamberlain's agonizing growls) and attractive red hair. He has even spawned his own Spin-Off one-man band The Almost to pander to his following.
 * And... The Almost was so successful that he left Underoath to focus on it.
 * Genesis got wildly popular after their bat-winged, flower-mask-wearing singer/frontman/spokesman/FaceOfTheBand Peter Gabriel left and was replaced with, well, the balding, stocky drummer of the band who sang a bit. Then the drummer went solo in 1981...
 * Limp Bizkit attracted a huge Hatedom, chiefly centered around Fred Durst. The only one who arguably escaped was Wes Borland, the guitarist with a penchant for weird facepaint. Just as a measure of how he was the best-liked member, when he first left Fred posted his personal email address on the band's website. Fans proceeded to email him and congratulate him for leaving the band.
 * The Story of Evil series features the evil princess' very litteral horse named Josephine mentioned only once in the whole series. A lot of fans' reaction after watching the series is, "Yeah but what happened to Josephine? We need to know!"
 * Apparently Gakupo kidnapped her for his harem in Venomania.
 * It's hard to be an Ensemble Darkhorse when associated with Rick Astley's Never Gonna Give You Up, but the literal version gives a lot of attention to the hyper-talented bartender.
 * LMFAO's robot dancer seems to have quite a few fans.
 * Both Robbie Williams and Bobby Brown were secondary members of their respective boy bands, Take That and New Edition, before gaining way more success as solo artists.
 * Whilst Sting was undoubtedly the Breakout Performer of The Police, drummer Stewart Copeland became the band's Darkhorse. His unique playing style influenced numerous musicians (Trey Anastasio and Les Claypool have called him a "mutual hero", and Taylor Hawkins has invited him on several Foo Fighters tours to play as a guest drummer), and Rolling Stone readers voted him the fifth-greatest drummer of all time in 2010.

Mythology

 * Anubis in more modern times. He wasn't that central to the original canon, but he's so much more interesting than the chief gods like Ra or Osiris. Also, it's hard to find a death god who's an okay guy. Also, he appeals more to Furries.
 * The same could be said for Hades (minus the furry part), who is another example of a god associated with death who was actually an okay guy. The Ancient Greeks were rather wary of him, naturally, but in modern times he gets a lot more appreciation... that is, if you are not Disney or Hollywood. This could be because he is a classic case of Dark Is Not Evil mixed with The Woobie, and/or because he was one of the only gods in the Pantheon who wasn't a complete jerk.
 * Disney tried to make Hades |unlikeable. Thankfully, they failed, and the movie was that much better for this "failure."
 * Hephaestus has become this nowadays. His main flaw (his hideous looks) makes him seem to be more of a Woobie than back in Ancient Greece, when he would have been viewed as repulsive, plus, as with Hades, he's downright saintly next to his uncles, aunts, and cousins.
 * It doesn't hurt that his purview includes 'technology'.
 * Ares/Mars was a very unpopular god for the Greeks, but the Romans claimed to be his descendants. It is worth noting that despite widespread modern misinterpretations, the Roman gods were not exact analogues of the Greek gods. Ares/Mars is a particularly notable case, as the Greeks saw Ares as the god of brutal warfare, while the Romans saw Mars as the god of warfare for the defense and spread of civilization. He even had an agricultural aspect leftover from an earlier Etruscan god and the fact that early Roman soldiers were basically drafted farmers. Some modern adaptations of Greek mythology also feature Ares in a much more positive light.
 * So long as you're not counting God of War as a "modern adaptation"... which it isn't.
 * Both Sun Wukong and Hanuman got a disproportionate amount of attention, so much so that the former is now considered the main character of his story. The relationship between the two is interesting, but it's no surprise that they fill this role as they both get their fair share ofBadass moments.
 * As for Hanuman, his Ensemble Darkhorse status has made him the most popular deity (alongside Lord Ram) in the Guyanese and Trinidadian regional variant of Hinduism.
 * Budai a figure in Chinese folklore, often revered as a deity in buddhism, is probably THE most popular buddhist deities in western countries. While he is sometimes considered a bodhisattva, people with little to no knowledge of Buddhism often mistake him for THE Buddha. Chances are if you see a statue or other representation of a Buddha in fiction, it will be this plump bald man with a big smile.
 * Loki of Norse Mythology has acquired far more popularity than he originally possessed, due to his traits of Chronic Backstabbing Disorder and (often deadly) practical jokes being more appealing to more modern audiences (generally the favourite was originally Thor, his policy of "hit it with a hammer first ask questions never" being, interestingly, less appealing to modern audiences).
 * Arguably, Loki was "originally" not as unpopular as he became when the Christians got hold of Norse mythology and associated him with Satan. The only extant versions of the Norse myths are the Eddas, which were written well after the Christianization of the mythos.

New Media

 * Mr. Mooshi from Conquering the Horizon was supposed to just be the first thing Evelyn ate. Instead the players decided to get on top of him and try to use pheromones to tame him. After that the QM did a good job making Mr. Mooshi a fun character (which was often actually Evelyn being a fun character and have 'dialogue' with Mr. Mooshi). There's more to Mr. Mooshi than that though, like the time he vomited up grass for Evelyn to eat at one of her low points.

Newspaper Comics
"Dogbert: A disturbing number of you have requested the return of Loud Howard. Loud Howard is one-dimensional. There is nothing clever or insightful about him. He is simply loud. It is a mystery why anyone would want more of this guy. Loud Howard: THEY LOVE ME!"
 * Common in long-running comics: Popeye was once a minor character in Thimble Theater.
 * Much the same happened with Barney Google and Snuffy Smith where the original hero (Barney Google) was displaced by a later, initially minor, character (Snuffy Smith).
 * Nancy was originally a strip called Fritzie Ritz until Fritzie's niece Nancy became more popular than the title character (a typical 1920s-30s-era flapper).
 * And given the popularity of "Aunt Fritzi" on The Comics Curmudgeon, it looks like we're coming full circle.
 * Blondie was originally about the adventures of single flapper Blondie Boopadoop, but eventually her suitor Dagwood Bumstead won her hand and became the central character.
 * Snoopy of Peanuts started out as a minor character and a more ordinary dog.
 * Pig-Pen was a massively popular character in the strip despite being hated as a one-off joke by Schulz. Schulz was eventually forced to include him occasionally throughout the 60's and 70's.
 * Mutts began with only Earl the dog and his owner Ozzie. Mooch the cat was supposed to appear for just one arc. Now he has at least as much importance and face time as Earl. As the cartoonist puts it, "You know how cats have a way of taking over the place."
 * Dilbert has at least two cases in which one-shot characters joined the main cast by popular demand: Ratbert and Catbert. Scott Adams hadn't even named the latter when he got deluged with emails for "more Catbert."
 * Dogbert once summed up this trope while discussing LOUD HOWARD:


 * Opus, the main character of Bloom County and two other comic strips by Berke Breathed, was originally intended to appear for one week-long arc, but after an enormous amount of fanmail, the author promoted him to a recurring character. Finally, after a huge fan response to one particular Sunday strip featuring Opus, he became the main character of the comic.
 * Bill the Cat started as a one-shot spoof on Garfield and Garfield merchandising. Ironic considering Bill's later merchandise empire.
 * Several Characters from Pearls Before Swine, including Zebra, Guard Duck, the Vikings...
 * ...THE CROCODILES.
 * Rosalyn the babysitter from Calvin and Hobbes was first created for a single brief story arc, but Bill Watterson surprised himself with her unique ability to completely intimidate Calvin, so several more babysitting stories (and one swimming class story) followed. In her final appearance she even got to literally beat Calvin at his own game and get him to go to bed without any hassle.
 * April from For Better or For Worse became this for the fandom, often seen as the Only Sane Man... which is odd because the creater didn't like her. At all.
 * A certain strip used to be called Robotman. Then it was Robotman and Monty. Now Robotman's retired and it's just Monty, but there is quite a large cast and entire story arcs are based on other characters.
 * Mac Manc Mcmanx/M3/M&M&M from Get Fuzzy. Come on, he constantly speaks in confusing British lingo, squats in Rob's house and gets detained at an airport for having a friend named Al Kayda. He's just awesome. Also, there's Chubby Huggs.
 * Kevin, the "Lost Bunny of the Apocalypse," has practically usurped the position of main character in Prickly City, especially since his 2010 election to the Senate and 2012 Presidential campaign.

Tabletop Games

 * Hans appeared exactly once on a single card in Magic: The Gathering, and never anywhere else, but the flavor text was popular enough that he got multiple references later on including a short story in the anthology Monsters of Magic (called "Ach! Hans, Run!"). Arguably, Norin the Wary similarly qualifies, having been elevated from the voice of cowardice on a handful of cards' flavor text to eventually receiving his own (also cowardly) creature card.
 * There's also Ib Halfheart, Goblin Tactician and, more famously, Jaya Ballard, Task Mage. Jaya Ballard's card has been known to win "best flavour text" votes on fan sites despite the card not actually having any flavour text (she supplies a solid number of fan favourite flavour text quotes on other cards).
 * In the Legend of the Five Rings CCG, Toku was originally an unaligned, free card with no abilities and no use other than being fed to demons. Fans enjoyed the idea of Toku so much that they started the "Toku for Emperor" movement, attempting to influence the game's interactive storyline. As a result, Toku became a major player in the game's storyline, going from a peasant who stole a dead samurai's sword to a real samurai, friend of the Emperor, Captain of the Imperial Guard, founder of a Clan, and (posthumously) a minor deity.
 * Dungeons & Dragons has a few examples. Inspired greatly by the example of Drizzt above, drow are a perennial favorite as Player Characters despite the race originally being Exclusively Evil. Future splatbooks expanded greatly on drow culture and options for drow players. They're even included as a PC race in the Fourth Edition Forgotten Realms setting.
 * This is lampooned in the webcomic Order of the Stick, where Nale's "Linear Guild" includes a Drow whose presence prompts the heroes to question, "Aren't Dark Elves evil?" Nale "explains" that that was before they were a player-character race; "The race now consists of nothing but Chaotic Good rebels struggling to throw off the reputation of their Evil brethren." "I thought you said they were all Chaotic Good?" "Details."
 * Another surprisingly popular race is kobolds, of all things. Despite their status as first-level Cannon Fodder (though their affinity for traps can make them more dangerous than you'd think), they've gotten a great deal of expansion in various splatbooks, including the 3.5 Edition Races Of The Dragon. One of the more infamous Game Breaker builds for the edition, "Pun-Pun", is a kobold.
 * It's kind of helped that the kobolds have been the setting's Butt Monkeys for so long that they've pretty much run all the way around on the opposite end of the sympathy scale to become woobies in their own right. Plus, nothing feels more satisfying than bringing down the BBEG with a small, scrawny lizard normally considered a CR of 1/6.
 * There is also a sort of Ugly Cute factor playing.
 * Which leads to then becoming utter badass Commandos.
 * Possibly based on this utterly brilliant session report.
 * The Tome of Magic Binder class is surprisingly popular considering the other 2/3s of Tome of Magic are the mechanically unplayable Truenamer and the mechanically odd Shadowcaster.
 * In a similar vein, "Complete Psionic" is widely panned as the worst of the "Completes" line released for 3.5. However, one class in the book (the Ardent) is acclaimed for its balanced play, appealing flavor and unique approach to psionics. The Ardent would eventually be adapted to 4th Edition as a psionic class.
 * Eberron gave D&D one of the more popular new races - The Warforged. Basically, they're Magitek Mechanical Lifeforms, and they've been generally well received by the D&D community. Even on /tg/, Warforged are generally quite popular. It's probably because, well, robots are just plain cool. As a matter of fact, Wizards of the Coast recently put up a free supplement for 4E Warforged, making them Canon Immigrants.
 * The Shifters were popular enough to make it into the fourth edition, as well; there is some Internet Backdraft among furry bashers, though.
 * If it's possible for a single game in a gameline to be an Ensemble Darkhorse, Changeling: The Lost from the New World of Darkness probably grabs the title.
 * To elaborate, Changeling was one of the limited series NWOD games White Wolf release, only meant to have the main source book and five supplements. From the get go the game was at a disadvantage; not only was it contending with Vampire: The Requiem, which was undisputedly the most popular NWOD game at the time, but it also was the revamped version of Changeling: The Dreaming, one of the least fondly remembered games of the OWOD. Combine that with the fact its subject matter (Fairies) lacked the universal appeal that, say, vampires and werewolves had, and it didn't bode well. However, when it came out sales peaked and the internet was filled with adoration and acclaim for the game and its setting. Sooon the Changeling fanbase was one of the biggest in the community and rivaled Vampire on fans and players. This huge influx of interest got the series three extra books and several more PDFs added to the line, making it one of the stand out titles of the NWOD.
 * In a similarly unusual turn of events, a piece of prose from the core rulebook of the New World of Darkness, "Voice of the Angel," has merited a stunning number of references throughout the line, up to and including the finale of a sample story in Saturnine Night and a new covenant in Danse Macabre.
 * Kharn the Betrayer of Warhammer 40,000 has been embraced by the fandom, declaring him to be a pretty fun guy to be around and focusing on him to the exclusion of all other Chaos characters. It helps that he has a highly exploitable battle cry: ""
 * A Downplayed version is the Khornate Daemon Prince named Doombreed. He has a surprising number of references in the background of the game (approximately four, compared to the number of one-shot characters given a single paragraph), and he has become something of a Mauve Shirt in the background and on /tg/. It's speculated that he was Genghis Khan before, and that everything from his daemonic mount to his fu manchu mustache is on fire.

Theater

 * Perhaps one of the biggest examples in theater is William Shakespeare's Falstaff, a buffoonish companion to Prince Hal in the Henry IV plays. The plays were intended to celebrate Henry IV, while Falstaff is written as a poor influence who must be shunned once the prince matures. Despite Falstaff's negative characterization, he proved a fan favorite. The audience's sympathy for the character is evident in Henry V, where his death is described in heroic terms. Finally Shakespeare decided to fully cash in on Falstaff's popularity by ripping him out of his previous continuity and plopping him in modern day Elizabethan times to star in his very own comedy, The Merry Wives of Windsor. An apocryphal story holds that Queen Elizabeth asked Shakespeare to write a play about Falstaff in love because he was her favorite character.
 * Let's just say that Shakespeare's true intention behind Hal's rejection of Falstaff, and which of the two is meant to be the hero, has been the subject of fierce debate ever since. (The hero is definitely not Henry IV, though; despite being the title role his part is very small.)
 * There have been reworkings of Henry IV which embody both parts one and two, that are named "Falstaff" the entire play is built then with Falstaff for the most part playing the jolly Pinball Protagonist
 * Shakespeare produced a few more darkhorses in his various plays:
 * Mercutio is the darkhorse of Romeo and Juliet. As the witty comic relief, he gets the lion's share of good lines before his death marks the play's turn into tragedy.
 * Many people adore Benvolio, if only because he has a cool name. In many screen adaptations, he has a far larger role than in the original—he even got to be part of the Beta Couple in Romeo X Juliet!
 * Hamlet features Hamlet's lover Ophelia, who has become an archetype of mad girls.
 * The witches in Macbeth certainly qualify, to the extent that some scholars believe several of their scenes (particularly those involving Hecate) were added by somebody else after the play was originally published and they had been established as popular characters.
 * While not being the central protagonist or the eponymous character of the play, Shylock remains as the most widely-recognized character in The Merchant of Venice.
 * Arthur Miller's play Death of a Salesman is considered one of the greatest American plays—not at all for the reasons Miller intended, but he knew why. Looking back, he wished he'd focused more on the character Biff, the protagonist Willy Loman's son.
 * A real-life example that catapulted the actor's fame: Miss Marmelstien, a piece of Christmas Cake who laments her lack of a beau from the little-known musical I Can Get It For You Wholesale. The character sounds like, and was intended to be, a supporting character - until they cast Barbra Streisand in that role, her first Broadway role, and she stole every scene she was in. Supposedly her last line of the show won her a standing ovation.
 * In the hands of a skilled actress, the Shark girl who sides with the men in the number "America" can be this and a One-Scene Wonder, though it's hardly applicable for every performance.
 * Cirque Du Soleil examples:
 * Mystere has the Red Bird (aka Firebird), who participates in the Korean plank/trampoline/fast track act but is primarily a dancing character who weaves in and out of the action. By 2006, this character was popular and recognizable enough that the show got a new logo that featured it, as you can see at the show's trope page.
 * La Nouba has a bird character of its own, the kooky dancer known as the Green Bird; she was upgraded to logo status around the same time the Red Bird was.
 * Charlotte in Thirteen is a minor character, who, with the help of a badass solo at the end of the musical can really steal the show.
 * Ariana Grande played her in the Original Broadway Cast.
 * Also, Archie deserves special mention, even though he's a bit more of a main character. Although this really depends on the actor.
 * A disproportionate amount of Starlight Express fan art and fan fiction centers on Electra's components, who are tertiary when compared to most of the cast.
 * The most popular character in Clifford Goldsmith's play What a Life was a very minor one, a dorky teenager named Henry Aldrich. The character of Henry got such rave reviews that NBC Radio decided to adapt What a Life into a radio series with Henry as the protagonist.
 * Enjolras and Eponine are two of the most popular characters in Les Misérables even though.
 * The ACT Theatre production of A Christmas Carol has this with the "Turkey Boy", who (of course) delivers the prize turkey to the Cratchits at the end, but is introduced much earlier than in the novel. Also, Mrs. Dilber the laundress (who also acts as an opening narrator in this version) and the "plump sister"(identified as Ms. Clackett here).
 * In First Date: A New Musical, recently premiered by the aforementioned ACT in collaboration with the 5th Avenue Theatre, the Waiter gets his own spotlight number in the form of "I'd Order Love".

Toys

 * Takua in Bionicle started out as the Featureless Protagonist of a little-known Game Boy Advance game. After he was again the main character in a very successful online game (moving from Featureless Protagonist to having his own identity only at the very end), his popularity exploded. In 2003, he was the star of his own Direct to Video movie where he became Toa Takanuva and was released as a toy set twice (once as Takua and once as Takanuva). Then he and the other 2002-2003 characters returned in 2008 (complete with new toy figures), with Takanuva being the star of the first Level 3 Readers book and having an online blog that narrated the events of the final (regular) book. And his was the largest figure. He was released again as a Stars set in 2010.
 * Also of note are the Toa Inika. When the story moved to a brand new location (Voya Nui) in 2006, LEGO decided that, rather than create six new Toa characters, they would just take probably the six most popular Matoran characters and turn them into Toa, via space lightning.
 * A very minor on-line game character, called Tiribomba, developed a small following, despite having done absolutely nothing to contribute to the plot. The reason for his popularity lies in his wicked awesome name.
 * The Alley Viper figure from the original G.I. Joe line has a huge cult following amongst GI Joe fans, to such an extent that it was quickly re-released within two years of its initial run in circulation.
 * Same with the Crimson Guard figures; this was most notable during the GI Joe Vs Cobra/Valor Vs Venom years, when Hasbro built a new Crimson Guard mold and opted to not release as part of the regular series, opting to make the figure a Toys 'R Us exclusive. To ease fan anger, the figure was largely released in a series of army builder sets, meaning fans buying the figure could build their own units without having to buy multiple figures.
 * Mimic, a garish green unicorn from the 1980s My Little Pony line, reportedly did poorly in sales in its initial run. On today's second-hand market, prices soar.
 * It's been speculated, though, that Mimic's poor initial sales are what made her so hard to come by, and are the reason for her value today.
 * Firefly may be the queen of this trope. From the moment she was introduced, she was arguably the most popular of all the ponies. Even though she wasn't in much of the series, she was depicted on a ton of merchandise. When Rescue from Midnight Castle was rereleased on video in the 1990s, it was renamed Firefly's Adventure, even though Megan is really the main character. Lauren Faust even based Rainbow Dash's personality on her. (She would actually be Firefly if not for copyright issues).

Web Comics
"Tarquin: It's weird, no matter how many people he kills, the audience still thinks he's lovable."
 * Midoribom AKA Racer from Bomberman Land Parody is quite popular despite only appearing in that one comic in the entire Bomberman fandom. He is featured the most though
 * Roast Beef, Ray and (to a lesser extent) Pat from Achewood were originally part of "The Dirtiest Guys in Town," a group of nondescript cats who hung out together in early arcs. Ray and Roast Beef later became the main characters of the strip and Pat a notable supporting character.
 * Fail-Druid and Rob from Ctrl+Alt+Del, despite the fact that they're supposed to be annoying, are the most beloved characters in the series. Largely because they have actual personalities, and aren't a bunch of Anti-Sue's.
 * Sasha from Sluggy Freelance, Riff's girlfriend for under two years out of the strip's 10+ year run, enjoyed lasting popularity despite not making any in-continuity appearances between mid-2002 and mid-2009.
 * There was also Bert, Torg's artist friend with a disturbing obsession with crotches. He proved to be so popular,
 * Most recently, Crushestro, one of the villains introduced in the "Paradise" arc, gained significant popularity due to his over-the-top mannerisms. He recently made a reappearance for another Breather Episode.
 * Branch, from Home On The Strange. This is how she started out - as a person even the other characters couldn't stand. A more unlikely Ensemble Darkhorse has never been seen, but exactly one sentence of Character Development made her The Woobie and a fan favorite.
 * Originally, Nale was supposed to be the only member of the Linear Guild who survived their encounter with the Order of the Stick. But fans latched on to the Psychopathic Manchild Thog, so Rich Burlew made him (and Nale's girlfriend Sabine) recurring villains.
 * Thog's status received lampshading here.

"Hacky, sensationalist TV pop psychologist who appeared in ONE LOUSY PANEL whose single-word catch phrase has been adopted by "Checkerboard Nightmare" fans."
 * Then of course there's O-Chul and That Guy With A Halberd.
 * Not forgetting Daigo and Kazumi Kato, formerly Soldier #1 and Soldier #2.
 * The MitD (Monster in the Darkness) is also a fan fave, and Mr. Scruffy could be considered a dark horse except he's actually very important to the plot (just not yet).
 * The Booted Wight, Tsukiko's right hand minion (and the unofficial face of her undead mooks) is also quite popular.
 * Cassie SinClair from The Wotch seems to have a much bigger following than main character Anne Onymous, despite her appearances in canon being rather sporadic.
 * This is probably due to shipping: Robin/Cassie is much more popular than Robin/Anne. Also, her sporadic appearances seem to help her avoid the Idiot Ball.
 * Also, in a less typical example, despite the main comic making Jason's receiving of a Gender Bender as a major running gag it seems to be more popular in fan work to apply it to Robin instead.
 * Robin makes the cuter girl.
 * Or maybe it's just because Jason's transformations were being overdone at this point.
 * Zexion from Ansem Retort is a prime example of this trope. Originally planned to be the straight man to Axel, he gradually became more of the Jerkass, and his popularity grew with it. By Season 2, his gradual descent into being a jackass had become a free fall. His popularity grew to the point that Season 3 focused entirely on him, he's featured in the intro image to the website, and is arguably the most popular character in the entire series.
 * A Darkhorse Race would be the Jägers in Girl Genius. Originally amusing background characters, they were so popular that they became a major plot element, and 4 joined the main cast.
 * More specifically, Da Boyz, a trio of Jägermonsters sent to find a remaining Heterodynes (plus Jenka). Also the Girl Genius Wiki has a suprising amount of support for the nyar spider, a small spider that appears in one comic, wraps up a bad guy for dinner, and is promptly squished. People were oddly happy when it turned out this was a species, not an individual.
 * Steve from Questionable Content really only exists to give Marten a male friend, but he has a loyal following that wonder what he's up to during his long absences from the comic. When the answers are like this, it's no wonder.
 * The fourth-wall breaking filler character "Sweet-Tits" became an instant favourite, despite only appearing twice and never being coloured or given a proper name.
 * And according to the results of a "most popular character" poll, the most popular character (by far, scoring twice as many votes as the runner up) is... ...Hannelore! It surprised the hell out of the author.
 * Kamikaze Kate from Misfile has managed to be far more popular than her number of appearances would seem to warrant.
 * Ozy and Millie has had a handful of one-shot, or even one-panel, characters who gained a fandom. They include Edwin the clueless juror, Emily the schoolgirl skunk, and Stevie the black cat. The latter two have reappeared on occasions when the cartoonist needed extra students, but they remain Flat Character.
 * Doctor Hot from Checkerboard Nightmare. The author rolled with it and expanded his role, to further fan approval, but that didn't mean he had to like it. As his cast page describes him:


 * In Irregular Webcomic we have the Allosaurus. First have a very few apperance, but fans grow very, very attached to him, and basically on of the answers that someone will always hack into any poll in the site.
 * In a fan poll, the most popular character was... Death of Insanely Overpowered Fireballs, surpassing by a wide margin even the author, Steve, and Draak.
 * In Dominic Deegan we have Caylin Bren, evil blonde leader of The Chosen. Caylin's head got exploded by Luna, but there's just enough evidence suggesting he could have lived through it that it didn't quiet his fans. He was also written into the maligned Snowsong story arc, appearing in several flashback strips.
 * Bren's popularity appears to have waned over time. Nowadays, the Ensemble Darkhorse of the series is Punchy Mc Stonefist, the dwarf who everyone remembers for punching Dominic in the balls, followed by the Time Abyss Magnificent Bastard Rilian (who arranged for the aforementioned ball-punching as a Secret Test of Character), Bort the Mongrelman, and Gerald, a smiley face made of newspaper clippings that acts as Quilt's Companion Cube.
 * Katherine from Wapsi Square, a fairly minor supporting character, developed a fanbase rivaling most others, prior to the major shift in subject and tone. Fan demand led to her being one of the few supporting characters who were carried over after the change; although her role remains minor.
 * Buwaro's Companion Cube treatment of his pet rock Thadius has rubbed off on the fans to a ridiculous degree. Who even lampshade themselves. (Warning: "degree" is NSWF if you work with silicon-based lifeforms.)
 * Bard from 8-bit Theater was only seen in a one-panel gag as the "fifth Light Warrior" who was unmade by Sarda before his birth. He is quite commonly mentioned in the comic's forum, with some members even managing to trick a few people that he actually was in the comic at first and the creator retroactively replaced earlier strips with Bard-free strips - a tactic the author actually pulled off on a smaller scale before.
 * There's also King Steve, the insane and utterly retarded Cloudcuckoolander ruler of Corneria, and the Dark Warriors. Despite their lack of plot relevance, they both get more attention than was originally planned, and the Dark Warriors also get, since they happen to look kinda like the Light Warriors.
 * Kingsonnn Dededoo from Brawl in the Family initially appeared in one of the gag-a-day strips, but became a fan favorite on the forums. He has since made at least one more appearence.
 * Dr. Lee, from Skin Horse by Shaenon Garrity and Jeffrey Channing. She was in one series, as the Meganekko repressed Mad Scientist and one of the antagonists, but she is still being requested by fans, and drawn in fan art,
 * Regina from Dan and Mab's Furry Adventures appeared for a single panel in a flashback, then got an almost-blank cast page a few years later. Her resultant fan following was... mind-boggling. Readers' minds were boggled right back when she finally appeared out of nowhere in 2009.
 * The fat Shetland Pony from Hark! A Vagrant! has developed quite a fan following, considering that he was created for a one-off strip about a horse pooping.
 * So much so that a limited edition run of Fat Pony figurines were made. They have all since been sold.
 * The Adventure Time episode "The Eyes" focuses on an unblinking fat Shetland Pony who, according to Word Of God, is based off of this character!
 * Given its very large Geodesic Cast and tendency to fall into Four Lines, All Waiting, there's quite a few of these in the Homestuck fandom, although to what extent you could call those characters "minor" is debateable. The Wayward Vagabond was one of the first though, and gained quite a large following even before becoming a playable character.
 * The best example would probably be Ms. Paint, a random background character in Prospit that became well-known due to her Punny Name and unique appearance, but has absolutely no bearing on the plot whatsoever.
 * Another good example would be Fedorafreak, a character who has "appeared" in the form of background messages on John's dad's PDA a grand total of maybe four times. There are people who roleplay as him.
 * All of the trolls in the series seem to be radically more popular among the fandom, judging by the staggering amount of fan art, fan fiction, and cosplaying there are of them as opposed to the actual main characters.
 * Nepeta is another good example. Despite being very popular among the fandom, and appearing in a ton of fanart, she's probably the least important of the trolls. All she's done that's of any significance is being Aradia's server player, and asking Rose to talk to Jaspersprite. The latter of those two leads to, but that's still a relatively minor event.
 * Jake English became one very quickly, and his popularity borders on Memetic Badass / Memetic Sex God at times. It probably helped that his debut finally gave some resolution to who the hell Jade's penpal was anyway.
 * The main character of Rose's book series, Calmasis, has to be the worst offender of this in the history of the webcomic. Possibly no more significant than a passing mention and possible foreshadowing of other events, s/he has hundreds of pieces of fanart and has already spawned several fan theories hours after their debut update. Yes, a character within a book within a webcomic who was only described in detail on one page has quickly risen to massive popularity, already rivaling several other main characters who were given thousands of pages to flesh out. Only this fandom could do this.
 * Much like Calmasis, an  suddenly garnered tons of fanart before speaking even a single line.
 * The Felt. Despite being a Quirky Miniboss Squad made specifically for the Midnight Crew Intermission, they became very popular among the fanbase. So popular that they may have increased their importance among the comic; Act 5 introduces Doc Scratch, a new member of the Felt, and reveals that Felt boss Lord English is a time-traveling demon with a connection to the Troll Universe.  Speaking of the Midnight Crew...
 * Problem Sleuth: the Midnight Crew debuted and appear exclusively in several donation commands, "[waging] merciless, donation-funded warfare against the protagonists in a non-canonical but nonetheless grand plotline.". They later became a fundamental part of the plot of Homestuck, both as themselves and as alternate universe counterparts. Such was their popularity that Hussie briefly gave serious consideration to doing a Midnight Crew adventure instead of Homestuck.
 * Not only do they appear, but their alternate reality selves play a big part in the comic. This also sets forth a very confusing game within a game scenario.
 * Lolrus from What Do You Do is incredibly popular for something that only appears like 7 times out of over 700 panels.
 * Selby from Woods for The Trees.
 * Erfworld has several, some of which the authors delight in putting in, even as background characters. Most notable is "Scarlett", the unnamed redheaded Unaroyal warlord who has since her first few appearances and continued to appear frequently. Also, Vurp, the last surviving Hobgobwin after Chapter One, and to a lesser extent Sizemore, the most underused Caster.
 * Now that Scarlett's been given a name (Sylvia), she may count as an Ascended Extra by virtue of this trope.
 * Yawning Squirtle from Sonichu. He's so much of an Ensemble Darkhorse that he has his own webcomic.
 * Boxbot is terrible. Nobody likes Boxbot. Except for those that do.
 * Ples Tibenoch of Hanna Is Not a Boy's Name already had a massive fanbase before he was even introduced into the comic, all based on a few doodles and lone illustrations from the author.
 * Don't forget the unnamed cashier from the liquor store! He appears in maybe 3 pages of the whole story, yet fans have latched onto him, affectionately dubbed him "CA$H MONEY", and you should just see how much fanart he has.
 * Mortifer has a few examples:
 * The best example would probably be Leonest. He was the first black marketeer the protagonists had to deal with, a demon-obsessed drug dealer. Thanks to his cool design and deadpan attitude, he became instantly popular, and was upgraded to secondary cast member (Though all he did was hang out with the protagonists at their office between missions/during the Beach Episode. It's implied that he started doing other work for SinTech that doesn't overlap with what the protagonists are doing).
 * A rather odd example would be Matthew. While ostensibly a member of the main cast, he barely got any screen time—only a small side plot about him stalking his brother's girlfriend that . Didn't stop Matthew from being more or less the strip's most popular character. spoiler: However, Matthew recently gained a lot more importance due to him becoming [[The Mole for Vlad. Amusingly enough, the reason for his betrayal was that he was never given anything to do—in other words, because he didn't get enough screen time.
 * Far Out There has Bridget and Alphonse. The pair of mute, superpowered zombie children were only introduced to be the sidekicks of a secondary character, but they've since become the most popular creations in the comic.
 * Last Res0rt has Sedja the Efreet, a character that lives in a bottle around Addy's neck. Despite only having a few pages where she's even seen in the comic, let alone in action... well, who wouldn't like a character you shoot out of a gun?
 * Zig Zag, the titular character's porn star boss in Sabrina Online, has gradually been taking over the strip, to the point that the December 2010 group of strips focuses on Zig Zag and doesn't feature Sabrina at all.
 * El Goonish Shive has Chika who won this status after five Q&A comics with her, even despite general "enough of Q&A" reaction on EGS forum.
 * Also, Rhoda, who didn't have much of a role until recently. Lampshaded here
 * Looking for Group has Richard, who is without a doubt the most popular character in the whole story.
 * Corasyn from Nothing Comes Naturally. An adorable little magenta Weasel Mascot with odd, robotic speech patterns.
 * Alexander Hamilton is not, by any means, a major character in The Dreamer. He showed up in the middle of Issue 9, played a small role, and was gone by the end of Issue 10. You would not know this from looking at his fanbase. Oh, the shipping!
 * Freakangels features 12 of the eponymous psychics, about eight of whom function as major characters. The spaciest and strangest of the lot, Arkady, is the most popular character with the fans. (Of course, she's also the only one who is perpetually sweet-tempered—the rest of the Freakangels range from deeply cynical to downright murderous.)
 * Cookie Monster from Gunnerkrigg Court has appeared in two comics and one Bonus page so far, but almost all of the comments on those pages are about her. Turns out, one of her roles was transition to the whole chapter in the Foley House (her style obviously is—and was confirmed to be—influenced by Foley kids).
 * Tempest of Domain Tnemrot gained a large following on her first page and when the story's focus switched to the main characters, there were complaints she didn't get more screen time.
 * Penny Arcade has Tycho's niece Anne, also known as Annarchy. While almost all cameo characters in Penny Arcade gain massive fan followings overnight, Anne deserves special mention, since when a poll was held to determine which minor character should get their own guest strip over Comic Con, Anne won by a huge margin.

Web Original
"Strong Bad: Oh, now this guy had some class. The Blacksmith, that guy was a good guy. I hung out with him after the cartoon; yeah, we had some good times..."
 * From That Guy With The Glasses:
 * The curtains, every time fanmail appears, there is always one on the end dedicated to the curtains. Unfortunately, Suede didn't take then with him after he moved (they were his parents', but still...).
 * Doctor Insano.
 * Nella! It really says something that all videos she's in get dozens of comments about on how awesome she is and how she should have her own show. And the Chick seems to be listening - Nella now shows up in almost every episode.
 * Linkara on That Guy With The Glasses. One of many contributors who joined the site in late 2008, and plucked from almost complete obscurity, he quickly rose to become one of the site's biggest draws in only a few short months. Part of this was his unique niche (he is one of two Comic Book reviewers on the site), part of it was his consistent schedule (and at first, he posted more than one video a week, because he had a backlog of video reviews from before he joined the site), and part of it was his Colbert Bump from Spoony, who became a frequent collaborator. As early as January/February 2009, there was talk of him headlining a "comics and animation" section of the site called "Four Color Fantasy" (later renamed "Inked Reality"), but in fact he's so popular he's still listed separately, as an individual, on the site, a distinction shared only by Doug, Lindsay, Brad and Noah.
 * takahata101 of Team Four Star ended up getting a lot of attention thanks in part to his portrayal of Nappa. Little Kuriboh would even lampshade his popularity by mentioning one of the best way to have a abridged series is having takahata provide a voice in the show.
 * Nappa from Dragon Ball Abridged has easily become one of the series most popular characters, to the point where he had been making occasional appearances as a ghost despite having been completely forgotten in the original work after his death. The Abridged version of the Abridged series lampshades this by giving Nappa the line "You will love me and quote everything I say!"
 * Dad from Awesome Video Games is very big with the show's fandom, to the point where they requested he get an episode all to himself. He eventually did get one with a larger focus on him, where he transformed the show into "Computer Entertainment Related Programming" to review Jack Nicklaus' Greatest 18 Holes of Major Championship Golf (misspelled as Jack Nicholson Golf in the episode title and the episode itself) on the NES.
 * Similarly, Deacon (Dad's actor) from Video Games Awesome has become inordinately popular for a guy who sits in the background and says relatively little, probably thanks in part to some residual Dad-ness.
 * Their only pop music reviewer, Todd in the Shadows, to a small degree.
 * In the Homestar Runner toons, Strong Bad started out as a villain who was always doomed to lose to Homestar. Now he's debatably the most popular character, and definitely one of the most recognisable.
 * To a lesser extent, there's Homsar. He first appeared as a one-shot gag to make fun of a typo, and over time, has been promoted up the ranks to become part of the main cast. HR's creators have joked about avoiding giving Homsar his own cartoon since they would never need to use him again.
 * Same goes for Senor Cardgage.
 * Trogdor and Stinkoman (Strong Bad's blue-haired anime counterpart) are also very popular with the fans. They even appear together in the fifth episode of SBCG4AP!
 * Also Eh! Steve from the Show Within a Show Sweet Cuppin' Cakes. Strong Bad insists that the main character is Sherlock, some kind of "mix between a cow and a helicopter" who is constantly trying (and failing) to get a worm out of the ground, and that Eh! Steve is a background character who delivers his Catch Phrase once an episode. Nevertheless, Eh! Steve is vastly more popular and a much more recognizable symbol of the show.
 * Teen Girl Squad is another good example.
 * Strong Bad Lampshades this, along with The Other Darrin in the email original. After the departure of "Original Bubs," his temporary replacement "Onion Bubs" became a fan favorite.
 * Onion Bubs! ONION BUUUUUBS!!!
 * Played with in-universe in Strong Bad's commentary for an old King of Town toon. He hates every single thing about it except for the Blacksmith.


 * Red vs. Blue has Caboose, for whom the writers originally had no real plans other than for him to be a catalyst to annoy Church. Once he devolved into The Ditz of the group, he became very popular with the fandom however.
 * From what you can tell by the amount of views for 6 of the Speed Paints for Fairy Foxes done by creator StickFreeks herself, Kai, Kiki, and Louie might be in that territory.
 * Flippy from Happy Tree Friends.
 * Flaky as well. The two are a Fan-Preferred Couple.
 * There is a fine example of this in Dr. Horrible's Sing-Along Blog: Bad Horse, who gets only a couple of songs and a brief cameo at the end. Nonetheless, he's become quite popular in the fandom.
 * Bad Horse, Bad Horse! He rides across the nation, the Thoroughbred of Sin!
 * Bad Horse's iron hoofs are made from Tony Stark's skin.
 * In the Loading Ready Run fandom, Andrew Cownden is extremely popular despite not being a member of the core Loading Ready Run crew. The reasons for this are most likely his acting ability, the infrequency with which he appears, and his awesome accent.
 * During Desert Bus for Hope, Roscoe the duck takes the dark horse title. It just wouldn't be the same without him.
 * Originally just a mention in the Whateley Universe, Aquerna has become this trope. She's one of the least powerful students at Whateley Academy, and became popular enough that one of the Canon authors is now writing Aquerna stories too.
 * The Irate Gamer has one in the form of the Wise Sage, even some of the fans who snark and insult the show say he's a redeeming quality, in part probably because he acts slightly better than Bores, another reason why fans probably like him is the fact the person who acts as the Sage doesn't defend Bores as much these days. Interestingly enough, the Sage doesn't appear after the Aladdin review, possibly implying that Bores is either not using him again, or the Sage was grabbing too much attention that he thinks is his.
 * He finally reappeared for a brief cameo in his Cool Spot review, but he didn't get any lines.
 * Chris has seemed to figure out his Darkhorse status and now he's shoehorning in Wise Sage appearances hoping it will make his videos "look better".
 * Rosa Fiametta seems to be one of the most liked characters for Survival of the Fittest v4 so far, alongside being a Memetic Molester/Memetic Sex God and Launcher of a Thousand Ships. As well Orn "Dutchy" Ayers, a free-loving, comic-reading, foreign very sensitive, Icelandic immigrant, who was held in high regard by many of the handlers before he even appeared for real.
 * Jared Clayton of SOTF-TV is also pretty popular, considering that he isn't even a contestant, just a mentor and has had all of one line (not even onscreen!) in the actual game. This is probably due to the in-character twitter the staff maintains for him, featuring snark galore.
 * Mr. Kwong, a teacher in v4. It's very unusual for a non-student to get much attention (either in or out of character), but you'd be hard pressed to find a handler that doesn't like him.
 * Con, from Kilplix N Friends, to the point where he has his very own video.
 * The HVGN's basic shtick is showcasing retro gaming's ensemble darkhorses.
 * Team Starkid, the group responsible for A Very Potter Musical and Me and My Dick, has Jim Povolo. Despite getting a lot of the bit parts, he manages to steal every single scene he's in.
 * The Godmonster of Indian Flats is more well known from Stuart Ashen's videos than the movie where he's the titular character.
 * The Metamor City Podcast has Artax, originally created as an expository engine to explain some of the more complex bits of the world's magic in universe, the fans have often cited him as a favorite character over several of the main characters.
 * Cal Chuchesta of The Needle Drop
 * Greg the Spider from Arby 'n' the Chief.
 * The Queen of Rogues and Robbers was originally supposed to be a one-shot villain in The Questport Chronicles, but has been brought back every year due to her popularity.
 * The Engineer from True Capitalist Radio. Many of the trolls who call into the show wish that he would host more than Ghost.

Other

 * Good, old rock, ain't nothing that can beat that.
 * Pluto, the former planet. The outrage when it was downgraded to planetoid was unprecedented.
 * Too bad the astronomers played paper.
 * Voice Actors are quite possibly the biggest example of an Ensemble Darkhorse when it comes to actors. The Animation fanbase online quite often love various Voice Actors for all the work they do in Animation (and to a lesser extent Video games) and are often guests in various conventions. Unfortunately often enough they are generally the only audience that these people truly have. Which the fact that often enough they get little pay and companies often seem to see them as nothing more than cheap disposable labor is considered all the more disheartening. But sadly if you talk about Voice actors to normal people chances are they most likely will have no idea what you're talking about. (The only exceptions are generally folks who either used to be/still are well known for screen acting.)
 * Unfortunately it doesn't help that often enough many vocal fans of Voice actors are young adults who are often not the Target Demographic of the shows they watch.
 * Mel Blanc came from the Golden Age of American Radio, where it was possible to become famous based solely on voice work. He also got a lot of his fame in front of the camera playing comedic characters and guest starring on variety shows. Lucille Ball, Orson Welles, and Jimmy Stuart also first became famous in radio. Even voice actors who weren't able to make the leap to the camera had fans with the older generations who remember the radio era. With that last group, it's less about being an Ensemble Darkhorse, and more about being a fading star as time marches on.
 * Japanese-wise, the darkhorse seiyuu would be Norio Wakamoto. When seiyuu these days about the younger people, especially those catering to the more Moe archetypes, there's this old school Cool Old Guy seiyuu who stockpiles about classic and awesome villain roles. Thanks to his epic hammy performance, he's still viewed as one of the greatest seiyuu in business despite being not really the norm of this age's seiyuu (a man and old), and a Memetic Badass (and Real Life Badass too).
 * If you remember the old commercials for Cinnamon Toast Crunch, you'd remember three bakers...but if you saw any now you'd see only one. Guess who was the most popular and soon became the Spotlight-Stealing Squad?
 * Some people speculate that Bob and Quienno aren't around anymore because Wendell killed them.
 * Linus the Lionhearted was a kids' cartoon/cereal commercial in the 1960s featuring the then-current Post Cereal mascots. All of the characters are forgotten, except one: Sugar Bear.
 * From Disney Theme Parks, Figment is undoubtably the most popular character at EPCOT, and the Hitchhiking Ghosts have become the unofficial mascots of The Haunted Mansion, despite only showing up near the end.
 * Uncle Ernie, of all people, has this in spades. Yes, the mean, creepy guy who actually ends up molesting the titular character (and possibly even others youngsters in "Tommy's Holiday Camp") is the most fan-loved character right after Tommy himself. One could argue that he's popular because The Movie version is played by the band's drummer, Keith Moon, and whoever's playing him usually hams it up for all it's worth, but still...Not bad for a gay, incestuous pedophile with arguable drinking problems who only gets two short musical numbers.
 * Not too far behind Ernie is Tommy's other abusive relative, Cousin Kevin.
 * The Acid Queen and the Local Lad/the Champ (no, he's not the Pinball Wizard...he's not Elton John, either) have their share of fans, too, despite being one scene/song wonders and the latter having little to no effect on the titular character or the plot. Again, this could be partially because their movie counterparts are played by Tina Turner and Elton John, respectfully, both of whom were quite popular at the time.
 * Oddly enough, it should also be noted that, for some reason, the Local Lad/the Champ (especially Elton's version) is considered to be The Scrappy by some of the fandom. Why that is seems to depend on who you ask.
 * Pluto in Milky Way and The Galaxy Girls, having quite a following compared to the other characters.

Real Life

 * Frequently happens in elections where unknown or unlikely candidates come out of the blue and sweep into a position of power. This is most likely because their unknown status means the media has not yet accumulated a warehouse of dirt to use against them.
 * Examples form US elections:
 * Both Barack Obama and John McCain were considered unlikely to even be allowed to run as their party's candidates in the 2008 US presidential election.
 * On that front, Obama is far more of a darkhorse than McCain. McCain has run for president before, lots of people knew who Mitt Romney was, and everyone knew who Hillary was. Most people outside of Illinois had never even heard of Obama until the middle of 2007. Plus, as many people, even Obama himself, have noted, if you had told people in 2005 that the next president would have the middle name "Hussein" (and a surname that's one letter away from "Osama"), they would have assumed you had a crappy sense of humor.
 * Similarly, Sarah Palin was virtually unknown outside of Alaska prior to the 2008 election.
 * Who would have through the 2012 Republican front-runners would include Newt Gingrich and Rick Santorum?
 * Through he was in no position to win the race, congressman Ron Paul was easily the most popular candidate in the 2012 elections to young people, and even to some in the left. Don't believe me? Just compare the numbers in a Romney or Santorum rally to the number of participants in a Ron Paul rally!
 * At the beginning of the 2016 primaries, nobody expected Donald Trump to be anything more than an also-ran. In late-May, he has the GOP nomination all but guaranteed. In November he won the presidential election the media was sure he would never win.
 * Dwyane Wade, drafted after Lebron James and Carmelo Anthony. Most people were only focused on James and Anthony and Wade barely got any attention. Today he is the only one of the three with a championship ring and finals MVP award.
 * The 2001 Seattle Mariners and Arizona Diamondbacks. No big stars and almost everyone was over 30 on the Mariners, who would go on to win the most games in an American League season ever and tie with the 1906 Chicago Cubs for most wins in a season in all of baseball. This coming from a team that had never gotten serious consideration in a post-season before and had never gone to the World Series. The Diamondbacks, meanwhile, were the oldest team in baseball and did what neither the Mariners or anyone else in the past three years could do - beat the Yankees and win the World Series,
 * Nobody expected the Spanish national team to win a World Cup anytime soon. Their weapons were fear and surprise and a ruthlessly efficient defense.
 * Just to prove Real Life is just as surreal as fiction, the only person who thought Spain would win was Paul the Psychic Octopus, clearly the Dark Horse of world cup pundits.
 * The Cheese-Eating Surrender Monkeys of 1998. France failed to make the World Cup in 90 and 94 and got into the 98 tournament only by hosting the dang thing. They shocked the world with one of the most dominating defenses ever (one non-PK goal for the entire tournament) and capped off their improbable win with a 3-0 win over supposedly invincible Brazil in the final.
 * Greece winning the 2004 European Championship. No one expected them to even win a match, let alone the tournament: they were 80-1 outsiders before it got underway.
 * Denmark winning the European Championship in 1992. They weren't even supposed to be in the tournament, but replaced Yugoslavia (who was excluded due to UN sanctions) at the last moment. Both players and trainer were thus utterly unprepared and treated the whole thing as an experience.
 * For other continental soccer/football championships - we have Iraq winning the 2007 Asian Cup (not only during the War, but also overcoming multiple continental giants) and Zambia taking home the 2012 African Nations Cup after a long penalty shootout against the Ivory Coast.
 * For the NHL, the Phoenix Coyotes have a surprisingly large fanbase, despite it's hot climate for the city. It also helps that the Coyotes are The Woobie of the NHL, having never won a playoff, but still loved. Well, at least in the U.S.
 * During the Sydney 2000 Olympic Games, Australian comedians H.G. Nelson and Roy Slaven, unimpressed with the games' mascots, unveiled their own mascot, Fatso the Fat-Arsed Wombat. Fatso became more popular than any of the official mascots.
 * David Freese had some fine, if not outstanding seasons for the St. Louis Cardinals before going absolutely nuts in the 2011 MLB playoffs, culminating in hitting the game-tying triple in the 9th and game-winning home run in the 11th during Game 6 of the World Series (with his team one strike away from elimination in the 9th, at that).