Likely voters

Voter segments in political polling in the United States consist of all adults, registered voters, and likely voters.

Political opinion polling in the United States usually surveys one of three population segments.

According to the American Association for Public Opinion Research, "there is a consensus in the polling community that it is better to report 'likely' voters than 'registered' voters". Reporting on a Pew study, the Washington Post has noted that polls of "likely voters" represent the "Holy Grail of polling" and are most likely to accurately reflect the outcome of an election.

An analysis of 2010 polling by Five Thirty Eight concluded that polls of "registered voters" that year tended to favor Democratic candidates by a factor of five percentage points over the actual results of the election, while polls of "likely voters" tended to favor Republican candidates by a factor of one percentage point over the actual results of the election. According to the Huffington Post this is because registered voters who are least likely to actually cast a ballot tend to be low-income voters, or persons living in urban areas, which are constituencies that tend to favor Democratic candidates.

Polls targeting "likely voters" generally begin with a list of known registered voters and then ask respondents a series of screening questions before the survey is conducted. Often this can simply be "are you going to vote on Election Day?" with respondents who answer "yes" to the question being included in the survey's final results, and those who answer "no" being excluded. In other cases, complex formulas that account for a variety of demographic and psychographic variables are applied.

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