Nate Silver is saying that Newt Gingrich and Mitt Romney each have about a fifty percent chance of winning South Carolina. Bear in mind that this is based on pre-Swingrich polls, but it's also unclear how much Republican voters actually care about Gingrich's sad, failed attempts at an "open marriage." If Romney wins this one, he's got it all sewn up. But if Gingrich wins, or if Gingrich can give the appearance of a win, the race is still on. (Bear in mind that barring some kind of freak accident, Romney is still going to win the Republican nomination—he's' got the organization, the money, and the party machinery behind him—but Gingrich could easily levy a South Carolina win into a challenge in Florida. After that, Romney will squash him like a bug, but a little extra competition among the Republicans is a good thing for Democrats.)