An independent voter, often called an unaffiliated voter in the United States, is a voter who does not align themselves with a political party. An independent is variously defined as a voter who votes for candidates and issues rather than on the basis of a political ideology or partisanship; a voter who does not have long-standing loyalty to, or identification with, a political party; a voter who does not usually vote for the same political party from election to election; or a voter who self-describes as an independent.
Voting systems outside of the United States, including the British parliamentary system, may include independent voters as being "floater voters" or swing votes.
The definition of an "independent voter" is controversial and fraught with implications.
The earliest concept of independents is of a person whose political choices, by definition, were made based on issues and candidates (due to lack of party affiliation). Furthermore, early studies of voting behavior conclusively demonstrated that self-identified independent voters are less interested in specific elections than partisan voters, poorly informed about issues and candidates, and less active politically. However, a contrary view emerged: The independent usually voted on the basis of deeply ingrained beliefs, attitudes and loyalties, and is more like the strongly partisan voter than any other voter (or the idealized "independent").
By the 1960s, scholars attempted to define the independent based on behavior, rather than party identification or loyalty. Focusing on ticket splitters, these studies depicted an independent voter who had the same level of political interest as strong partisans and who voted largely based on the issues with which they strongly agreed and/or disagreed. However, by focusing on voting behavior, this definition of the independent ignored non-voters. Critics claimed that the independent voter is merely a subset of the larger set of independents, which should also include non-voters. Studies also found that voting and not-voting is deeply affected by the particular candidate running in an election. Voting, therefore, is more reflective of what candidate is running—and therefore a poor measure of partisanship.