Well, it's upon us. The superest Tuesday since Super Tuesday itself. It's make or break day for the Clinton campaign. To a lesser extent, I think it's make or break for the Obama campaign as well.
Clinton obviously needs to do well tonight. She's invested the last hopes of her campaign in the idea that the Giuliana strategy will work if it's done out of desperation in the middle of the race. Bill has said she needs to win Texas and Ohio in order to stay competitive. While the latest polls show her with a marginal lead in Ohio and a slim lead in Texas, it's not looking terribly optimistic. (And let's be honest. Rhode Island and Vermont don't really count.) If Hillary doesn't win both states tonight look for her to be gone by the end of the week. The pressure among Democrats to have a nominee already will continue to build and resentment toward her will continue to build if she's seen as hanging on to a hopeless campaign.
For Obama, the stakes are also pretty high tonight. As I've written before, he has yet to show that he can really put Clinton away. He's had his opportunities (I'm thinking New Hampshire), but hasn't been able to get the job done. If he falls short yet again, the questions about his killer campaign instinct will get much louder. While I don't buy the argument that not winning one of the big states in the primary means he won't be able to win them in the general election (do we really think that California might go Republican?), Obama does need to eventually win a battleground state just to show that he can. If he falls short again, it adds credence to the idea that Hillary is the fighter we want in the general election and it gives her a reason to stick around for another two months.
P.S. For an adictive good time, check out CNN's Delegate Counter Game. Run through the various election night scenarios and see what happens to your favorite candidate's delegate count. It's very enjoyable in an OCD politics junkie kind of way.