Politically, the concept came to the United States in the nineteenth century when it was first applied to James K. Polk, a relatively unknown Tennessee politician who won the Democratic Party's 1844 presidential nomination over a host of better-known candidates.
Perhaps the two most famous unsuccessful dark horse presidential candidates in American history are Democrat William Jennings Bryan, a three-term congressman from Nebraska nominated on the fifth ballot after impressing the 1896 Democratic National Convention with his famous Cross of Gold speech (Bryan would go on to receive the Democratic presidential nomination twice more and serve as United States Secretary of State), and Republican businessman Wendell Willkie, who was nominated on the sixth ballot at the 1940 Republican National Convention despite never having previously held government office and having only joined the party in 1939.
Senator Bernie Sanders is another classic example of a dark horse candidate, whose grassroots campaign in the 2016 Democratic Party presidential primaries came much closer than initially expected to toppling front-runner Hillary Clinton for the party's presidential nomination.
[10] In the United Kingdom, Jeremy Corbyn was considered a "dark horse" candidate when he ran for the 2015 Labour Party leadership election; despite struggling to secure enough nominations from the Parliamentary Labour Party to stand as a candidate, he won the leadership in a landslide.
[15] In Iran, Masoud Pezeshkian, a little-known "dark horse" candidate, was allowed to run by the Guardian Council and won a surprising victory in the second round of the 2024 Iranian presidential election.