Since a majority of undecided voters are breaking toward McCain, I see the most likely scenario to be; Obama wins the popular vote and losses a close electoral college vote.
This will be closer than Bush v. Gore in 2000 (BTW - the last time we won a national championship in football was the last time the Republican lost the popular vote but won the electoral college).
McCain gets 271 electoral votes with surprise wins in CO and MN, also winning toss up states FL, MT, ND, OH, IN and NC.
If that scenario plays out McCain gets 271 and wins the closest election in history.
This is not wishful thinking either. This is a very likely scenario.
If I'm wrong, I'll be more than happy to eat my crow.
Obama has outspent McCain 4-1, which is HUGE when we're talking about hundreds of millions of dollars.