I was really impressed with how well he presented himself and how presidential he sounded.
I was really impressed that he controlled the urge to say, "Hell no!" when asked whether he'd consider an Obama/Clinton ticket, but at the same time he didn't come out and lie about it. He didn't say, "Oh sure, I'd definitely consider her as my running mate. I think about asking her to drop out of the race on a daily basis, in fact, and the reason that I do is because I want her as my running mate because I relish the thought of spending the day with her every day for the next four years." That's a fine line to walk, and he walked it very well. He said no without saying no, and that was very politically savvy.
And she answered the question even better: "what he said."
