Just days before the primary polling starts, the GOP presidential race is so unsettled, there's a plausible scenario that gives any of the top four candidates—and even the trailing Fred Thompson—the nomination. Politico plays out what would have to happen for each of them to prevail. Romney needs Iowa; if he gets it, with New Hampshire a quick follow, he's on a roll.
Huckabee needs Iowa, too, to get a pass for New Hampshire, to carry him to the Southern primaries, where he'll be strong. Giuliani might just have the name recognition and the funds to fly without Iowa or NH, though it's never been done. McCain is back from the dead on the strength of improvement in Iraq, and Thompson, if he took third in Iowa, might just be able to hang on to battle Huckabee for the South.