For the complete documentation index, see llms.txt.Skip to main content
In most democracies, the choice of who appears on the ballot is at least as important as the election itself. If both candidates are centrists, the election produces a centrist. If one party nominates an extremist, voters face a fundamentally different choice. The nomination process shapes the menu.
The United States has the most open and elaborate nomination system in the world. Most other democracies leave candidate selection to party leadership — a committee vote, a members-only ballot, or simply the party leader's decision. The US hands it to ordinary voters through primaries and caucuses, a system that emerged from Progressive Era reforms in the early 1900s designed to wrest control from party bosses.
The result is a nomination process that takes over a year, costs billions of dollars, and involves dozens of individual state contests — a grueling test of organization, stamina, and fundraising that may or may not select the best candidate for the general election.
Primary elections work like regular elections: voters go to a polling place, cast a secret ballot, and leave. They're administered by state governments. Turnout is typically 15-30% of eligible party voters.
Primaries come in flavors. Closed primaries (New York, Florida) restrict voting to registered party members. Open primaries (Wisconsin, Virginia) let any voter participate in either party's primary. Semi-closed primaries allow independents to vote but not registered members of the opposing party.
Caucuses are party-run meetings where voters physically gather, discuss candidates, and vote — often publicly. Iowa's caucuses were historically the first contest and received enormous media attention despite representing a tiny, unrepresentative electorate. Caucus turnout is much lower than primaries (often under 10% of party registrants) because they require hours of participation on a specific evening — favoring the elderly, the passionate, and the organizationally supported. After 2020 controversies, Iowa lost its first-in-the-nation status for Democrats, and the trend has been toward replacing caucuses with primaries.
Delegates are the currency of nomination. Each state contest awards delegates — bound to vote for the winning candidate at the national convention. A candidate needs a majority of delegates to win the nomination. If no one reaches a majority, the convention becomes 'contested' — though this hasn't happened since 1952.
Iowa and New Hampshire traditionally vote first, giving outsized influence to two small, predominantly white states. A strong showing in these early states generates media momentum ('the Big Mo') and fundraising surges that can propel a candidate from obscurity to frontrunner.
Super Tuesday — when 10-15 states vote on the same day — is typically the decisive moment. Candidates who survive Iowa and New Hampshire face a national test of organization and resources. In 2020, Joe Biden's come-from-behind victory on Super Tuesday — after finishing fifth in New Hampshire — was powered by endorsements from Pete Buttigieg and Amy Klobuchar who dropped out days before.
Front-loading is the trend of states moving their primaries earlier to gain influence. This compresses the calendar and favors well-known, well-funded candidates who can compete nationally from the start. Long-shot candidates who relied on retail politics in small early states find the window narrowing.
In other countries: UK party leaders are chosen by party members (Conservatives) or a combination of MP nominations and member votes (Labour). Germany's chancellor candidates are selected by party congresses. France uses a two-round open primary that any voter can participate in. None are as lengthy or expensive as the American system.