I have no doubt that the best pollsters have good methods for determining who is, and who is not, a “likely voter”, i.e., not merely asking whether they intend to vote, but whether or not they know their polling place, whether have they voted in past years, etc.
But I’ll bet some pollsters aren’t that careful. And as Newsbusters’ Matt Sheffield reminds us, a lot of Americans will tell pollster that they’re certain to vote… and won’t: “Of those who were verified as not having cast a ballot in 2010, 65 percent told Pew that they ‘always’ or ‘nearly always’ vote.”
He cites a Pew study:
To assess the accuracy of the information in the databases, household information in the databases for survey respondents was compared with answers given during the survey.
Those listed as registered in the voter database were overwhelmingly likely to report themselves as registered in the survey (93%). However, 60% of those for whom there was no record of active registration in the database said they are registered to vote.
Respondents to the survey were not asked if they voted in the 2010 congressional elections, but were asked how frequently they voted.
Among those flagged in the database as having voted in 2010, 94% said in the survey that they always or nearly always voted.
Those for whom the database shows no record of a 2010 vote were less likely to say they always or nearly always vote (65%), including only 41% who say they always vote.
One of the recurring mantras of the title character on the medical drama “House,” was, “everybody lies.”
Perhaps we don’t need to be quite so cynical. But clearly, a significant portion of respondents lie to pollsters.