On December 4, 1844, Polk defeated the Whig nominee, Henry Clay of Kentucky another former Speaker of the House, making him the President-elect.

Polk would remain Speaker for four more years until he left Congress to run for governor of Tennessee which he held for one term before his defeat in 1841.

As the ballots continued Lewis Cass's delegate count eventually overtook Van Buren's, but his lack of experience prevented him from taking the nomination.

For the vice-presidency Silas Wright was initially nominated, but he refused and was replaced by Pennsylvanian Senator George M. Dallas after he defeated John Fairfield on the third ballot.

Polk's support of Manifest Destiny successfully distanced him from the "southern crusade for slavery" which allowed him to receive support from the Western Democrats and anti-slavery Northerners giving him a surge in voter turnout for the Democratic party.