Primary election types by state
Primaries choose each party's candidates. Who can vote in them depends on the state and sometimes the party. This map covers congressional and state primaries; presidential primaries can follow different rules.
- Open (14)
- Semi-closed (8)
- Closed (17)
- All candidates on one ballot (4)
- Varies by party (7)
Open (14)
Any voter can pick one party's primary on the day.
Alabama · Georgia · Hawaii · Michigan · Minnesota · Mississippi · Missouri · Montana · North Dakota · South Carolina · Texas · Vermont · Virginia · Wisconsin
Semi-closed (8)
Party members vote in their party's primary; unaffiliated voters can choose one.
Arizona · Colorado · Maine · Massachusetts · New Hampshire · New Mexico · North Carolina · Rhode Island
Closed (17)
Only registered party members can vote.
Connecticut · Delaware · Florida · Illinois · Indiana · Iowa · Kentucky · Maryland · Nevada · New Jersey · New York · Ohio · Oklahoma · Oregon · Pennsylvania · Tennessee · Wyoming
All candidates on one ballot (4)
Top-two or top-four primaries, or a majority-vote system.
Alaska (Top-four primary, then ranked-choice voting in November) · California (Top-two primary: all candidates on one ballot, the top two advance) · Louisiana (Majority-vote system: all candidates on one ballot; a majority wins, otherwise a runoff. U.S. House races moved to it in 2026) · Washington (Top-two primary: all candidates on one ballot, the top two advance)
Varies by party (7)
Each party sets its own rules.
Arkansas (Democrats: open; Republicans: semi-closed) · Idaho (Democrats: open; Republicans: closed) · Kansas (Democrats: open; Republicans: closed) · Nebraska (Democrats: semi-closed; Republicans: closed) · South Dakota (Democrats: semi-closed; Republicans: closed) · Utah (Democrats: open; Republicans: closed) · West Virginia (Democrats: semi-closed; Republicans: closed)
Questions and answers
What is an open primary?
One where any registered voter can vote in a party's primary without being a member. You still vote in only one party's primary per election.
What is a top-two primary?
All candidates, from every party, appear on one ballot, and the top two advance to November even if they're from the same party. California and Washington use it; Alaska advances the top four.
Can independents vote in primaries?
In states with open or semi-closed primaries, yes. In closed-primary states they generally must join a party by a deadline.
Primaries in the glossary · The 2028 primary calendar
Source: Ballotpedia, "State primary election types" (August 2026), by party. Some states Ballotpedia counts as closed let voters declare a party at the polls or change it shortly before.