What is a political caucus?

A political caucus is a meeting of party members or supporters held to discuss candidates, build party platforms, organize political activity, or, in presidential nominating contests, to select delegates to the party's national convention. The term caucus has multiple meanings in American politics. The most common meaning today is the meeting of party members in a state or local area, particularly in the context of presidential nominations.

In a presidential caucus, party members gather at a designated time and location to publicly indicate their preferences among candidates and to select delegates to higher-level party conventions. Caucuses traditionally take longer than primary elections, often lasting several hours, and require voters to be physically present rather than simply casting a private ballot. The most famous caucus is the Iowa caucuses, which traditionally were the first contest in the presidential nominating calendar every four years. The Iowa caucuses gave the state outsized influence over presidential nominations for decades.

The Democratic Party changed its calendar starting in 2024 to begin with South Carolina rather than Iowa, partly in response to concerns about Iowa's lack of demographic diversity and 2020 caucus mismanagement. The Republican Party has continued to hold the Iowa caucuses early in its nominating process. In Republican caucuses in Iowa, voters typically gather at precinct meetings, hear short speeches in support of various candidates, and then vote by secret ballot. The results determine how Iowa's delegates to the Republican National Convention are allocated.

In Democratic caucuses (in years when they have been held), voters traditionally aligned themselves in groups supporting different candidates. Candidates needed to reach a viability threshold (often 15 percent of those present in the precinct) to win delegates. Voters supporting non-viable candidates could realign with another candidate or sit out, leading to extensive negotiations on caucus night.

Beyond presidential nominations, the term caucus also refers to legislative groupings within Congress and state legislatures. The Democratic Caucus is the formal group of all Democratic senators and representatives. The Republican Conference is the equivalent group on the Republican side. Caucuses select party leadership, develop policy positions, and coordinate strategy.

Specialized caucuses also exist within Congress for specific groups or issues, such as the Congressional Black Caucus, the Congressional Hispanic Caucus, the Congressional Asian Pacific American Caucus, the Congressional Progressive Caucus, the House Freedom Caucus, the Problem Solvers Caucus, and many others. These caucuses bring together members with shared identities or policy concerns to coordinate on legislation and other matters. Many states have moved away from caucuses to primary elections in recent years, citing higher participation and easier voting, leaving caucuses for presidential nominations to a smaller number of states.