Rep. Michele Bachmann's (R-Minn.) slim chance to win the Iowa Republican caucuses on Jan. 3 receded even further Wednesday night, as her Iowa campaign co-chairman, state Sen. Kent Sorenson (R), jumped ship to endorse Rep. Ron Paul (R-Texas). A short three hours after appearing at a rally with Bachmann, the evangelical Christian, socially conservative Sorenson showed up on stage with Paul, saying he was going all-in for the libertarian icon. "When the Republican establishment is going to be coming after Ron Paul, I thought it is my duty to come to his aid," Sorenson explained. What's really behind this 11th-hour defection? Here, three theories:

1. Sorenson knows Bachmann is going to get crushed
Bachmann was already tied for last place in the polls, and now Sorenson's "new land-speed record for a political defection... pretty much kills the Bachmann campaign," says Joe Klein at TIME. Indeed, Bachmann really "hasn't shown much to offer as a serious contender" since a standout performance at an early debate, says Bryan Preston at Pajamas Media. A late surge never materialized, and Sorenson probably "panicked once he realized that he was on a sinking ship." But he chose a tenuous life raft, bailing "from one candidate who won't win Iowa to another who might but probably won't, and won't win the nomination. Interesting choice."

2. The Paul campaign bribed him
After Sorenson's defection, Bachmann shot back: "Kent Sorenson personally told me he was offered a large sum of money to go to work for the Paul campaign." (Team Paul denies any financial motivation in Sorenson's decision.) I initially chalked up Bachmann's bribery allegation to "the momentary and understandable hyperbole in the immediate aftermath of betrayal," says Ed Morrissey at Hot Air. But then Sorenson's former campaign manager said Sorenson had told her a similar story, so maybe Bachmann's right after all. A direct payoff, or promise of some sort of steady "salary," would at least "explain why he would leap from Bachmann to Paul, two campaigns that have diametrically opposed viewpoints on foreign policy and immigration."

3. Paul was always a better fit for Sorenson
Sorenson may be a home-schooling, anti-gay, evangelical darling, but "it's not entirely surprising" that he decided to back the libertarian Paul, says Patrick Caldwell at The American Prospect. Sorenson is a fiscal conservative as well as a social conservative — "he once sponsored a bill to return Iowa's government to the gold standard," for example — and he's worked with Paul's Campaign for Liberty group in the past. And there's a personal element as well: Paul helped raise money for Sorenson in his 2009 state Senate campaign. If, as Sorenson says, he believes the GOP has "a clear, top-tier race between [Mitt] Romney and Ron Paul," it makes a lot of sense that he backed Paul.