Hillary is counting on a huge win in Pennsylvania to show that she has momentum, and that she is the one who can win the "big states." The polls taken in the last week, however, suggest that the race in the Keystone state is now a dead heat, with Clinton fading fast from the double-digit lead she was showing in March.
Hillary cannot lose Pennsylvania and maintain viability as a candidate.
And remember the superdelegates? The ones Hillary is counting on to put her over the top? Well, it seems that in the last two months, Obama has picked up 69, while Clinton has lost two.
Additional Update: I met Sam Gamgee! This past Saturday, I attended my Congressional District's Democratic Caucus as a delegate for Obama. Much to everyone's surprise, the official speaker on behalf of Hillary Clinton was none other that actor Sean Astin, star of the Lord of the Rings films. Democracy is awesome.
Also: Historians weigh in: G.W. Bush is the worst President ever.