In open primary

Open primary

An open primary is a primary election that does not require voters to be affiliated with a political party in order to vote for partisan candidates. In a traditional open primary, voters may select one party's ballot and vote for that party's nomination. As in a closed primary, the highest voted...

 elections in the United States

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

, crossover voting refers to a behavior in which voters who normally participate in the primary of one party instead vote in the primary of another party. The behavior typically happens when the nominee of the one party is a foregone conclusion or when a candidate in one party's primary has an appeal to the voters in another party

The motives for crossover voting are sometimes strategic. Thus crossover voting has been used by voters to cast votes in the party a voter is opposed to in order to nominate a candidate which can be more easily beaten by the candidate the voter actually supports.

Some consider crossover voting to be a form of electoral fraud

Electoral fraud

Electoral fraud is illegal interference with the process of an election. Acts of fraud affect vote counts to bring about an election result, whether by increasing the vote share of the favored candidate, depressing the vote share of the rival candidates or both...

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