The reason Republicans tiptoe so carefully around the birther question is that birthers constitute a significant portion of the Republican base. Tim Pawlenty is meeting with a prominent one in New Hampshire:
Likely GOP presidential hopeful Tim Pawlenty is set to have dinner in New Hampshire this week with the sponsor of what’s been dubbed the Granite State’s “birther” bill.
The former Minnesota governor, who has been aggressively courting the tea party vote to burnish conservative credentials in recent weeks, will visit New Hampshire again to help boost his standing among the first-in-the-nation primary voters. Pawlenty is scheduled to have dinner Thursday with Granite State Patriots Liberty PAC leader Jerry DeLemus and his wife, Susan DeLemus, a freshman New Hampshire state Representative.
Susan DeLemus is the lead sponsor of a House provision that would require presidential primary candidates to provide birth certificates, in addition to a sworn affidavit that they are at least 35 years old and have lived in the United States for 14 years, as called for in the Constitution to qualify for the presidency. ...
Asked Wednesday afternoon specifically about the meeting with DeLemus, Pawlenty spokesman Alex Conant responded: “The governor is meeting with lots of people while he’s in New Hampshire, some public and some private. … As for the bill, the governor hasn’t seen the legislation.”
He's not for it, he's not against it. If pushed into a corner by a journalist, he'll probably say he personally believe Obama was born here and/or we should move on to others issues, and will resolutely refuse to condemn birthers.
The birther movement occupies a similar space in the GOP as does, say, handgun control in the Democratic Party today. It's an idea that a large portion of the base supports, but is unpopular with independents, so leaders with any national responsibility or ambitions have to distance themselves from it without alienating its passionate advocates. The difference, of course, is that advocacy of gun control is not a paranoid, factually wrong belief.