I am not sure that anyone has brought this up before, but I believe that one of the reasons Hillary is not going to go anywhere after tonight is the newly begun Rezko trial and its potential to eliminate Obama from a serious general election run.
I am not saying that Obama has done anything illegal (at this point he has just been proven to be stupid and careless in his dealings with Tony Rezko and that is probably all that will come of it), but we have to remember that the facts are not out yet in this case and there could potentially be a bombshell dropped in court that would essentially prevent Obama from being a viable candidate in the fall, thus switching all the superdelegates (another reason they are there) and giving the nomination to a still "contending" Hillary.
Now, before anyone responds with "all the facts are out and Rezko is a HRC talking point", I want people to recall what happened with Roger Clemens and the Mitchell Report. Up until that report came out, Clemens name was rarely ever (if ever) mentioned seriously among the suspected steroid takers in baseball, now his name is tarnished and it is quite possible that he could face jail time (or at least a federal perjury trial). I am not, however, comparing Clemens to Obama (since Obama is not accused of any "wrongdoing"), but am saying that there is a BIG difference between a newspaper investigation and a federal trial in which deals are cut and witnesses are compelled to talk.
Personally, I think that the trial will have little, if any effect on the Obama campaign, but I do believe it will be an unspoken reason that the Clinton campaign continues at least through PA and probably all the way through the primaries if for no other reason than to keep the pledged delegate vote "close" in case a PR disaster strikes.