Open vs. Closed Primary Elections in the U.S.
Created by FindLaw's team of legal writers and editors | Last reviewed March 18, 2020
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Voting in the election of governing officials is one of the defining features of a democratic republic. In the United States, voters have a unique opportunity to participate in electing federal, state, and local officials by casting their own ballots in elections.
Different elections have their own objectives and procedures. Additionally, each state has unique rules for conducting elections. All of these factors determine what the voting process will entail for voters in any given election.
In the U.S., states can have open or closed primary elections or variations of both. However, it is important to first know the difference between primary elections and general elections before we discuss the differences between open and closed primary elections.
Primary Elections vs. General Elections
Partisan primary elections — often known as "primaries" — are elections held within a political party before general elections. In general, the main purpose of a primary election is to narrow the field of candidates within a political party. Voters accomplish this goal by electing a single candidate to represent their party.
Once each party elects a candidate to represent them, those candidates move on to compete against each other in the general election.
General elections are elections between each party's elected candidate. The goal of general elections is to select a candidate to fill the office for which the candidates are running, e.g., the presidential office, gubernatorial office, etc.
Open vs. Closed Primary Elections
Finding the best-qualified candidate to represent a party is challenging, and different states have different ways of choosing them in partisan primaries.
Open Primaries
When we talk about open primaries, we are essentially talking about primary elections that are open to all voters, regardless of their political party affiliation.
Open primaries give voters the greatest amount of freedom when casting their vote because they can privately vote in either party's primary.
Voters in areas with open primaries can vote for a candidate in their party, or they may choose to vote on the other party's ballot, crossing party lines. Open primaries also allow independent and third-party voters to participate in primaries without registering with the party.
Closed Primaries
Unlike open primaries, voters in areas with closed primaries have to officially register for a political party before they can vote in the party's primary.
Once the voter has registered with a particular party, the voter can only participate in that party's primary election. For example, Republicans can only vote in the Republican primaries, and Democrats can only vote in the Democratic primaries.
An important feature of the closed primary system is that it forces voters to affiliate with a political party before they can vote in a primary election. Therefore, independent and non-affiliated voters are generally forced to affiliate with either the Republican or Democratic party to cast their vote in a primary election.
Why Do Some States Use Closed Primaries?
If open primaries provide more voters with a greater amount of choices, why do some states have closed primaries?
Proponents of closed primaries say that it strengthens a party's ability to nominate a candidate of their party's choosing when outsiders are not allowed to participate.
Another concern is that open primaries allow members from opposing parties to vote across party lines. They can attempt to elect a candidate the opposition party is more likely to beat in a general election.
This process is known as "raiding" and is rare, as most voters want to vote for their party instead of against it.
Semi-open vs. Semi-closed Primaries
Some states hold primaries that are neither strictly open nor completely closed. Depending on how they are carried out, these not-quite-open-nor-closed primaries are known as semi-open or semi-closed primaries.
Semi-open Primaries
In a semi-open primary, voters fill out party-specific ballots, but they do not have to officially affiliate with either party. If an independent or non-affiliated voter wants to vote for a Democrat in the primary election, they vote with a Democratic ballot when they arrive at the voting booth.
Likewise, if they want to vote for a Republican in the primary election, they cast a Republican ballot.
Semi-closed Primaries
In semi-closed primaries, voters still have to affiliate with a party before they can vote. But, unlike a truly closed primary system, voters do not have to officially affiliate with a party until they vote.
Voters can generally change their party affiliation on Election Day. However, many states, like New Hampshire and Colorado, still require voters to officially affiliate with a party before they can cast their ballot.
Some states allow each party to choose what type of primary it will have. In Alaska, for example, the Republican Party holds semi-closed primaries while other parties hold open primaries.
Legal Support for Voters
Because so many states conduct their primary elections differently, it can be worthwhile for voters to look into their state's primary election procedures before heading to the polls.
If voters suspect their right to participate in any type of election have been unjustly limited, they should consider contacting an experienced attorney in their area.