dark horse

American  

noun

• dark horses
  plural

1. a racehorse, competitor, etc., about whom little is known or who unexpectedly wins.

2. a candidate who is unexpectedly nominated at a political convention.

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dark horse British  

noun

1. a competitor in a race or contest about whom little is known; an unknown

2. a person who reveals little about himself or his activities, esp one who has unexpected talents or abilities

3. politics a candidate who is unexpectedly nominated or elected

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dark horse Cultural  

1. An unexpected winner. In politics, a dark horse is a candidate for office considered unlikely to receive his or her party's nomination, but who might be nominated if party leaders cannot agree on a better candidate.

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dark horse Idioms  

1. A little known, unexpectedly successful entrant, as in You never can tell—some dark horse may come along and win a Senate seat. This metaphoric expression originally alluded to an unknown horse winning a race and was so used in a novel by Benjamin Disraeli (The Young Duke, 1831). It soon began to be transferred to political candidates, among the first of whom was James K. Polk. He won the 1844 Democratic Presidential nomination on the eighth ballot and went on to win the election.

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Other Word Forms

Noun Inflected Forms

• dark horses
  plural

Etymology

Origin of dark horse

First recorded in 1825–35

Example Sentences

See Examples For:

dark horse

I don’t know how much of a dark horse that one is, but that’s my pick for show.

From Los Angeles Times ● Jun. 18, 2026

Now, on his main-draw debut on the Paris clay, Jodar has emerged as a dark horse for the Coupe des Mousquetaires.

From BBC ● Jun. 1, 2026

“All that is to say, I was charmed by ‘Pizza Movie,’ my dark horse pick.”

From Los Angeles Times ● May 21, 2026

Blyth also called Rieder a bit of a "dark horse" on whether his decisions would shift from Powell's.

From Barron's ● Jan. 26, 2026

This card, the one with the dark man on a dark horse, this means jealousy, and this one, sorrow.

From "The House on Mango Street" by Sandra Cisneros

Related Words

• also-ran
• long shot
• sleeper
• underdog