Washington — As with many aspects of U.S. politics, national party conventions and their roles in the race to the White House have evolved over time to serve the changing needs of the electorate. The U.S. Constitution does not reference political parties and is equally silent on how to select candidates to the nation’s highest office, but mechanisms arose and adapted to fill that vacuum.
Beginning in 1796, members of the U.S. Congress who identified with one of the political parties of the time met informally to agree on their party's presidential and vice presidential nominees. This selection system, known as the "King Caucus," continued for almost 30 years but broke down in 1824 as the nation’s westward expansion decentralized political power.
National nominating conventions gradually replaced King Caucus as the means for selecting party nominees. In 1831, a minor party called the Anti-Masons met in a Baltimore saloon to choose candidates and write a platform (statement of beliefs and goals) on which its candidates would run. A year later, Democrats met in the same saloon to select their nominees.
Since then, the major parties and most minor parties have held national nominating conventions at which state delegates vote on the party’s nominees to the offices of president and vice president and on the party’s policy positions.
For most of the 19th century, the presidential nominating conventions, although attended by many party members, were controlled by party leaders. These political bosses used their influence to select their state's convention delegates and steer the delegation’s votes.
Populist demands for reform in the early years of the 20th century led to primary elections that allowed voters to select convention delegates. By 1916, more than half the states were holding presidential primaries.
However, after World War I, party leaders successfully pushed back, persuading many state legislatures to abolish primaries. By 1936, only a dozen states continued to hold presidential primaries. The pendulum swung back in the middle of the 20th century, when television allowed candidates to communicate more directly with voters and heightened voter interest in the nominating process.
With each succeeding decade, primaries expanded and the party’s nominee became more likely to be determined well in advance of the national convention, based on the results of state primaries and caucuses.
Depending on the laws of the state, primary voters may cast a ballot for a party's presidential nominee and a slate of "pledged" delegates or may vote for the presidential candidate with delegates to be chosen later to reflect the vote.
Under the caucus system, voters who live within a relatively small geographic area (known as a precinct) assemble in a church, school, library or private home and vote for delegates who are pledged to support specific candidates for president. Those delegates, in turn, represent their precinct at a county convention, which chooses delegates to attend the congressional district and state conventions. The delegates to these conventions ultimately elect delegates to represent the state at the national convention. Although this process typically takes months to complete, the candidate preferences are determined in the first round of voting.
The actual size of any state's delegation to the national nominating convention is calculated on the basis of a formula established by each party that considers the state's population, its past support for the party's national candidates and the number of elected officials and party leaders currently serving in statewide and national office from that state. The Democratic Party’s allocation formula results in national conventions that have about twice as many delegates as those of the Republican Party.
Changes in the presidential nomination process have decreased the importance of the party's national convention. Today, the presidential nominees usually are determined by the voters many weeks in advance of the conventions. An eventual nominee sometimes even chooses a vice presidential candidate before the convention meets.
However, the national conventions continue to serve some valuable functions in the U.S. election process. They provide a nationally televised stage for reaching voters, draft the party platform, showcase the party’s rising stars (like Barack Obama in 2004) and allow party members to come together behind a candidate and build enthusiasm for the campaign.
That enthusiasm — the willingness to contribute time and money to a candidate and encourage others to do the same — might well be the single most important factor in determining who will occupy the White House for the next four years