Rick Perry surprised a lot of people with his decision to stay in the presidential race after the Iowa caucus, including his own staff. Nate Silver says that this is because he either a) is doing it for deeply personal reasons; or b) has been shown a strategic path to come back and win.
Let me expand upon a third theory that I hinted at on Twitter yesterday:
Mary Kaye Huntsman and Anita Perry have been friends for years, having met when their husbands were both Republican governors. Since their husbands have both become presidential candidates, their friendship has grown and they talk almost daily.
If Jon Huntsman does well in New Hampshire, he may be well positioned to do well in South Carolina. If Jon Huntsman does poorly in New Hampshire, he will have to drop out of the race. Should the former happen, Rick Perry could drop out of the race after New Hampshire but before South Carolina to endorse the surging Huntsman, arguing he too is a solidly conservative guy focused on jobs with a conservative record as governor. If Huntsman drops out, he could endorse Perry lending credibility to his campaign as well as Huntsman's suprisingly credible South Carolina organization.
Sound crazy? Both women have shown that they are among their husbands' most trusted and influential political advisors. If Perry's campaign in South Carolina is largely focused on tearing down Romney, Santorum and Gingrich and making the argument that you need a governor who has a conservative record, he could be doing it not only for himself but as a proxy for Huntsman.