Obama might loose like Al Gore-won the popular vote but lost the presidency. Clinton is strong and we've lots of time to go. Anything can happen. Obama's time of clean shaven, fresh guy is over. From here on, it's all scrutiny and down low dirty politics.
The only magic he's got is-anything Hillary says, he'll dodge it by saying "Oh! It's becaues I'm BLACK". The same stereotypical African American's defense mechanism.