Obama also said he was surprised some of those attacks weren't brought up by his opponent at the debate Tuesday night at Belmont University in Nashville, Tenn.

"I am surprised that, you know, we've been seeing some pretty over-the-top attacks coming out of the McCain campaign over the last several days, that he wasn't willing to say it to my face. But I guess we've got one last debate. So presumably, if he ends up feeling that he needs to, he will raise it during the debate."