Haberman and Martin and Allen scoop:
According to two sources familiar with the plan, the Texas governor will remove any doubt about his White House intentions during his appearance at a RedState conference in Charleston.
It's uncertain whether Saturday will mark a formal declaration, but Perry's decision to disclose his intentions the same day as the Ames straw poll — and then hours later make his first trip to New Hampshire — will send shock waves through the race and upend whatever results come out of the straw poll.
Well, yes. After just a few hours I've met numerous Republican voters who are leaning towards a candidate like Michele Bachmann but want to know more about Perry. There's a write-in option on the Ames straw poll, which we'll all now be watching to see how well he does. And a the news of a possible, hard-won Bachmann victory is immediately blunted, so she has to establish her credibility again.
Unless this is a repeat of the Barbour/Daniels about-to-jump-in head-fake, of course.
UPDATE: A third party group is already running ads in Iowa boosting Perry.