First off, I'm surprised that it appears close today. As I said after Wisconsin, I thought March 4 voters would recognize that at this point, it's either Barack Obama or a Brokered Convention, and they're terrified of the latter. But that notion has not dominated discussion this week.

Obama has often outperformed the polls, but if he does again today, I think fear of the brokered convention is at least part of the reason.

Clinton appears to have a bit of a bump going into today. But there was a tightening before Wisconsin, where Obama ended up winning big.

I thought the press narrative going into Wisconsin was worse for Obama (nothing but "plagiarism") than now (a flurry of charges on both sides that likely blurs for voters). I would presume that allows fear of brokered convention to surface.

But Ohio is particularly hard-hit economically and is less impressed by a fresh face. Obama likely needs more time to become familiar to do well there.

So I'll give the edge to Obama in Texas, the edge to Clinton in Ohio. And I bet the superdelegates press Clinton hard after that, to let her know they won't save her in Denver, and to step aside.