Bob Barr, Spoiler
Bob Barr has accepted the nomination for the Libertarian party. I'm pretty sure he represents the saner wing of the party, the one that defends individual liberty and the free market, and not the Peikoff branch who thinks we have the right to invade "uncivilized" nations who have not had the fortune to read Atlas Shrugged.
And there goes a good 5%-10% of McCain's base. McCain is not a libertarian by any stretch of the imagination, and a party desperately seeking legitimization is going to vote Barr. So who's left to vote for McCain?
Burned Hillary supporters
Shit, even the fascists aren't going to go for McCain, and he can kiss the right wing Christian vote bye bye as long as Hagee, Parsley and Dobson tell them to stay home.
Oh, sweet November is almost here.