A state senator who was at one time the chairman of Michele Bachmann's Iowa campaign, switched his allegience to Ron Paul on Wednesday night, just hours after attending a rally for Bachmann. Republican Kent Sorenson showed up to a Paul rally unannounced to say that he was now backing the Texas Congressman, then jumped on stage to offer his public endorsement.

The news came as a shock to both sides, since Sorensen (who was one of Bachmann's earliest supporters in Iowa) was at a Bachmann campaign rally earlier in the day, but said he couldn't give a speech because he had just come from the dentist and his mouth was numb. A few hours later, he called Bachmann on the way to the Paul rally to tell her that he was jumping ship. After arriving at the Paul event at the Iowa fairgrounds, he called a Paul staffer from the parking lot and asked, “Do you guys want me on board?”

In a statement, Bachmann accused Sorensen of being paid off by the Paul campaign, a charge that Paul's camp denied. Sorensen says he still "adores" Bachmann and his choice was "excruciatingly difficult," but that he sees Paul as the only candidate who can "take out" Mitt Romney.

It's a particularly galling blow to Bachmann's Iowa effort, which is now on its last legs with less than a week to go before the caucus. Even Rick Santorum has pulled ahead of her and the move signals that she's no longer worth even a token vote. It will be interesting to see if other members of the "anyone but Romney" camp will begin to rally around a single alternative candidate, or if it even makes sense for Paul to be that guy. Paul may be the best bet to take Iowa, but it remains to be seen if he can extend his run to other states and actually make a dent in Mitt's inevitability machine.

Update: Sorenson expands on his decision to switch sides, which he made 10 minutes before going on stage, to Time magazine. He also calls Mitt Romney a "frugal socialist."