Yes, I think it would. If Obama ran unopposed then he would be "Obama, the man who ran against nobody, and won." But now he will be "Obama the giant killer", "Obama, the man who took on the great Conservative hope, and creamed him by 45 points". All Alan Keyes is doing is adding to the Obama mystique. He's going to build Obama up to be something bigger than he has any right to be. He's the best thing to happen to Obama since the DNC speech.
So which is Keyes, a buffoon or a giant?