It seems most people are thinking the votes in the four primary states voting today--Ohio, Rhode Island, Texas, and Vermont--could go any way for the Democrats. Obama's favored in Vermont, and Clinton had been favored in Rhode Island (though her lead has shrunk a little recently). The big-ticket states of Ohio and Texas seem really up in the air. It seems as though Clinton has reversed Obama's momentum over the past few days and has expanded her polling lead in Ohio, and, in Texas, where Obama had been leading, she is now eking out narrow leads. Real Clear Politics averages for both Ohio and Texas show Clinton's poll numbers strengthening. Rasmussen's daily tracking poll shows Clinton achieving her first nation-wide polling lead over Obama in three weeks. Of course, this primary season has delighted in frustrating pundits. Obama's been able to outperform significantly his polling numbers in past races, but so has Clinton (as Kaus reminds us). Clinton probably has the edge in Ohio, but Texas is more complicated due to the fact that its primary includes both a conventional voting-booth primary and a series of caucuses.

So what could happen after today? That's hard to say. Certainly, if Clinton wins both Ohio and Texas (or at least wins the popular vote in Texas) and wins in Rhode Island, she seems very likely to stay in. A recent poll shows Democratic voters want her to stay in the race even if she wins only Ohio or Texas. If she loses both big? There seems like there would be significant pressure on her to bow out. If she loses both by a little? She may decide to keep on fighting. Her people are keeping an eye on the Rezko trial--which seems already to have damaged Obama's relationship with the press--and maybe even the Canada-NAFTA flap. If it seems like some scandal could derail Obama's campaign, Clinton's more likely to stay in no matter what the results are today.