- Democratic congressional and state primaries: closed
- Republican congressional and state primaries: closed
- Democratic Presidential primary: mixed
- Republican Presidential primary: mixed
- Voters may or may not choose to affiliate with a political party, however, affiliation with a party is required to vote in primary elections.
- 11% of Maryland voters are unaffiliated with a political party.
Details of voting in congressional and state primary elections:
- State law gives political parties the power to choose whether to hold open or closed primaries. Any changes must be submitted to the State Board of Elections six months before the primary.
- Both parties have always elected to hold closed primaries, therefore, voters must affiliate with a party in order to vote in that party's primary.
- Voter registration closes 21 days before the primary election.