David Gergen: “Mitt Romney is clearly trying to prove -- his campaign is trying to show that he's going to take the fight to Obama.”

If he comes out and throws cold water on this, then I don't think it goes anywhere.

You can't out-Nixon Nixon very easily, but Donald Trump has.

I think a lot of Americans do see it as disqualifying. And they're worried about it.

If he had a receptive audience, and I will tell you, when everything -- when all the facts were to come out, it would be like Nixon and the tapes.