I am not too worried.
Why? He's peaking too early. He'll crash and burn.
Agreed he will crash and burn...after Hillary shoots him out of the sky. She is using Obama as a straw man, to keep money and publicity from flowing to Edwards and Gore, at least one of whom could give her a serious challenge in the primary.
Once this is safely a two-person race, Barrack will look like a porcupine with all the knives stuck in his back (and as a bonus, if Hillary paints him as a "religion of peace" sympathizer, she can make herself look almost tough on national security).