This explains why GOP leaders refuse to give an honest answer about Obama's birthplace:

Birthers make a majority among those voters who say they're likely to participate in a Republican primary next year. 51% say they don't think Barack Obama was born in the United States to just 28% who firmly believe that he was and 21% who are unsure.

The GOP birther majority is a new development. The last time PPP tested this question nationally, in August of 2009, only 44% of Republicans said they thought Obama was born outside the country while 36% said that he definitely was born in the United States. If anything birtherism is on the rise.

Weigel thinks the poll "suggests that birtherism has become another screen for extreme partisanship." Bernstein wants a more detailed analysis of those who believe the birther myth.

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