If a stock was super dark horse, it will rise, otherwise, it can't be called the super dark horse!

若某股是超级大黑马，则必将上涨，否则，也就不能称其为超级大黑马！

youdao

In politics,a dark-horse candidate is someone who is not well known to the public.

VOA: special.2009.07.12

Sometimes,a dark horse unexpectedly wins an election.

VOA: special.2009.07.12

Sony is also promoting the film to Academy voters as a contender for Best Picture, and the film is probably a very valid dark horse contender for a nomination.

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The third candidate, Michael Badnarik, a computer-programmer from Texas, entered the convention as a dark horse: unlike the other two hopefuls, he had not even rented a room for his campaign headquarters.

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He could even turn out to be a dark horse for the presidency.

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