Maryland's primary elections are usually closed, meaning that only voters affiliated with a party may vote in that party's primary. So independent voters and voters registered in a party that does not have a primary may not vote in another party's primary. However, in 2000 the Maryland Republican Party held an open primary.
The deadline to change from one party to another or to change to or from unaffiliated or independent status is 9 p.m. on the Monday 12 weeks prior to the primary election. This does not apply to voters who have moved from one Maryland jurisdiction to another since the last general election. These voters have until three weeks before the primary.
- Many candidates but few fireworks in Maryland's congressional primaries (By Ben Pershing, Washington Post) "Regardless of who wins the Republican primary, we are confident voters will agree that the only way to fix Washington is to elect representatives with the independence to make decisions based on facts and common sense, not on politics," said Kratovil campaign manager Jessica Klonsky.