I apppreciate your question about the measure on the poll of respondents' vote in the last presidential election. Historically, our polls and others have found that respondents do not always accurately recall who they voted for in the past and much depends on the popularity of whoever is living in the White House. There was quite a good discussion of this phenomenon on Slate recently, which you might want to take a look at. We use the question for purposes of internal analysis but do not rely on it in any substantive way. We are more likley to rely on poll respondents' self reported party identification or political ideology when it comes to looking at differences between political groups. Thank you for being such a careful reader of The New York Times and for your interest in The New York Times/CBS News Poll.
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