Caucus vs. Primary: How Caucuses and Primaries Work

A caucus is a nomination process where voters in precincts, districts, or counties meet in public and vote for their preferred candidates via a public ballot. Caucusing dates back to early United States elections, when it was impractical to maintain multiple polling places, particularly in rural areas where residents were spaced far apart. Reduced travel times and modern technology have mitigated the original reasons behind a caucus system; however, both the Democratic Party and the Republican Party continue to operate nominating caucuses in multiple U.S. states. The Iowa caucus is the most famous of the presidential election season, and it has traditionally been the first nominating contest in an election year.

Party members gather at a central location at a caucus, such as a school gymnasium or a party office. They then demonstrate their public support for their preferred candidate, often raising their hands as a ballot is read aloud. In most cases, a candidate's supporters cluster together in one part of the room. The goal is to gain enough votes to send one or more delegates to the party's official nominating convention.

In most Democratic caucuses, a candidate must receive fifteen percent of the votes to earn delegates. If, after an initial ballot, a candidate does not muster enough votes to claim delegates, they are deemed to be nonviable. Their supporters are free to support another candidate who could still possibly claim delegates. As such, a voter may arrive at a caucus intending to give their vote to one candidate but end up supporting someone else because their first choice was nonviable. Republican caucuses generally operate with a winner-takes-all model.

In the United States, a primary election is a pre-election in which candidates are selected to run for office. This formal primary election process, regulated since 1890, is unique to the United States and occurs on both the state and national levels.

Primary elections are elections that happen at the party-level and help political parties choose the strongest candidate to move forward. As candidates from within one party debate each other, they can grow and refine their platforms and strategies to become stronger contenders in the general election. Presidential primaries, in particular, can greatly affect a campaign.

For voters, primary elections work similarly to general elections: you register to vote and, on election day, visit your polling place or, if voting absentee, mail in your ballot. Whether you can vote in a primary election, however, depends on your state and political party affiliation.

After the votes have been counted, it’s not over. In an indirect primary, these results are taken to a convention where delegates representing voters cast the final votes. Many Republican state primaries are decided on a winner-take-all basis, where the candidate with the most votes receives all the delegates. The Democratic primaries are usually decided by proportional representation, giving every candidate who hits a certain threshold at least one delegate. (Superdelegates, introduced by the Democratic Party in the 1980s, are unpledged and unelected delegates.) Once all of the delegates have voted, a candidate is chosen and it’s on to the general election.

There are several types of primary elections with varying rules and regulations. Some types of primary elections include:

1. 1. Closed primary: In a closed primary, only registered party members can vote, which promotes party unity. Connecticut, Delaware, Florida, Kentucky, Maine, Maryland, Nevada, New Mexico, New York, Oklahoma, Oregon, Pennsylvania, South Dakota, and Utah have closed primaries for at least one party.
2. 2. Semi-closed primary: A semi-closed primary is open to party members and unaffiliated voters not registered with a political party. A very similar system, called a semi-open primary, makes the choice of primary ballot even more private. Arizona, Colorado, Idaho, Kansas, Massachusetts, Nebraska, New Hampshire, New Jersey, New York, North Carolina, Oklahoma, Rhode Island, South Dakota, Utah, and West Virginia use semi-closed primaries for congressional and state-level elections.
3. 3. Open primary: In an open primary, anyone may vote for a party's primary candidates, regardless of their party affiliation. Still, voters may only vote in one party's primary. Thus, if a Republican chose to vote in the Democratic primary, they could not later vote on a separate ballot for GOP candidates. Alabama, Alaska, Arkansas, Georgia, Hawaii, Illinois, Indiana, Iowa, Michigan, Minnesota, Mississippi, Missouri, Montana, North Dakota, Ohio, South Carolina, Tennessee, Texas, Vermont, Virginia, Wisconsin, and Wyoming all have open primaries for at least one party.
4. 4. Top-two primary: All primary voters receive the same primary ballot, regardless of party affiliation, in a top-two primary system. The top two vote-getters from this primary election advance to a general election, even if they both represent the same party. Note that this system can only apply to state and local offices. This is the system used in Washington, California, and Nebraska for state legislative elections, which are nonpartisan.

Traditionally, the New Hampshire primary election is the first primary contest in an election cycle. However, New Hampshire falls behind caucus-based Iowa as the first state to vote for presidential elections.

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