So Hillary and Edwards are both unbeatable?
As of today(and I realize a lot can and will change, this is more of a anti-pd liking mccain topic):
Ohio has turned insanely democratic and thrown out nearly every elected republican in 2006 so as of 2007 it is a Democratic lock.
Arkansas is 100% loyal to hillary even though it is deep south. She has almost endless connections there. She'll win Arkansas even if she ran as a Nazi. Alone that is enough to make her unbeatable. I don't know anything about Iowa and Missouri.
Hillary is unlikeable but a much better politician and campaigner than Kerry was still. Seeing how bush has dropped from 50% approval when Kerry ran to under 30% there is no feasible way for her to lose those unless something changes. And Ohio is now a lock, again unless something changes.
All Democrats need to win is keep the Kerry states and pick up Ohio. Ohio threw out nearly all republicans in 2006. They have became strongely democrat, not just due to national problems but the local Ohio republican party became a complete corrupt mess.
For a Democrat to lose, Hillary or anyone they will have to mess up. BADLY.