Dark horse

A dark horse is a little-known person or thing that emerges to prominence, especially in a competition of some sort, or a contestant that seems unlikely to succeed.

The term began as horse racing parlance for a race horse that is unknown to gamblers and thus difficult to place betting odds on.

The first known mention of the concept is in Benjamin Disraeli's novel The Young Duke (1831). Disraeli's protagonist, the Duke of St. James, attends a horse race with a surprise finish: "A dark horse which had never been thought of, and which the careless St. James had never even observed in the list, rushed past the grandstand in sweeping triumph."

The concept has been used in political contexts in such countries as Iran,Philippines,Russia,Egypt, Finland,Canada, and the United States.

Politically, the concept came to America 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. Polk won the nomination on the ninth ballot at his party's national nominating convention, and went on to become the country's eleventh president.

Other successful dark horse candidates for the United States presidency include:

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.

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