State conventions for nominating candidates were first held in the early 19th cent. The first national convention was held by the Anti-Masonic party in Baltimore in 1831. Formerly the candidates for president and vice president were selected by a party caucus, i.e. a meeting of influential members of Congress, and they favored their colleagues. In 1832 the Democrats nominated Andrew Jackson at a national convention. The Republican party held its first national convention in 1856, when John Frémont was chosen as the presidential candidate.
Candidates were often selected only after many ballots had been taken. This was especially true of the Democratic party, which, until 1936, had required successful nominees to win two thirds of the delegates' votes. Thus, Stephen Douglas was nominated on the 59th ballot in 1860, Woodrow Wilson on the 46th ballot in 1912, and John W. Davis on the 103d ballot in 1924. The difficulty of gaining agreement on a candidate at conventions led to a unique feature of the American political scene: the dark horse—a candidate with little or no formal support before the opening of the convention, who succeeded in gaining the nomination. Since 1960, however, national conventions have tended to ratify front-runner candidates increasingly determined by delegates won in primaries and state caucuses, rather than select from among evenly matched rivals. National political conventions have thus changed from their initial function as nominating mechanisms into mobilizers of party energy for the upcoming campaign.
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.