Closed Primary

• States vary in the type of primary elections that they hold. A closed primary system allows only people who are already affiliated with a political party to vote for candidates of that particular political party. Under the closed system, voters cannot change affiliations at the primary. The nominee of a particular political party is the person who gets the majority of votes compared to other candidates on the ballot.
  
  

Open Primary

• In an open primary, a voter does not have to declare an affiliation to a particular party and can thus decide to vote in either of the party's primary elections. Virginia is an example of a state that holds open primary elections. However, if both parties hold their primary elections on the same day, then Virginia law states that an individual cannot vote in both parties' elections on the same day and therefore has to choose to vote in one.
  
  

Modified Closed Primary

• The state of California has embraced a modified closed primary system. Essentially the same as a closed system, voters can vote in the primary of the party to which they are already affiliated. The difference is that the political parties can decide whether people who did not state party affiliation during voting registration may or may not vote in each party's primary.