Direct primary elections represent a significant shift in the electoral process that started in the early 20th century. Before the rise of direct primary elections, nominees for the general election were selected by political party leaders. In a direct primary, voters choose a party's candidate in a preliminary election.

Traditional Nomination

Candidates for the general election were traditionally selected at political party conventions, notes the "Encyclopedia of American Political Parties and Elections." Party delegates, selected by local party groups, attended these conventions. The political party leaders played a major role in selecting nominees, and special interest groups were another significant influence.

Early Election Reform

According to "The American Direct Primary," the shift to nominating candidates through a public preliminary election followed a change in the American electoral system. In the late 19th century, the United States moved to an electoral system in which the government, not the parties, printed ballots and managed voting in the general election. A movement to democratize the nominating process by having voters elect the candidates emerged.

Direct Primaries

Starting with Wisconsin in 1903 and culminating in broader reforms in the 1970s, direct election primaries became a standard way of selecting party nominees for the general election. However, party caucuses, conventions and indirect primary elections also continue, especially in the presidential nomination process, in which it's common for parties to select delegates to participate in the party's national convention based on the results of a primary in which voters express their preferences for a presidential nominee.