I'm not so sure the answer's as straightforward as you might think.

Don't forget that Hillary's been thoroughly "vetted" by the Republican smear machine. Unless they can come up with something new, the voters are going to tune out what they perceive as a tired old whine. The end result of more than a decade of hating Hillary has simply solidified the enmity of the base, but it's hardly knocked her out of the running with everybody else. In fact, I think it's fair to say that the hatred of Republicans has made her look better to non-Republicans. The enemy of my enemy etc.

McCain, on the other hand, is relatively less well-known. A household name, but he hasn't been put under the microscope as intensely as Hillary. I think there's more chance of surprise revelation about McCain than about Hillary. And McCain has the additional handicap of Republican dislike of "RINOs", and it's not inconceivable that his own party could turn on him. If you want to talk about getting beaten to a pulp, a moderate without the support of his party will be dead meat.

You're right that this is just a hypothetical matchup from a polling question. But it's the kind of question that gets people thinking, and if a lot of people relish the prospect of two strong candidates, for a change, it could become a self-fulfilling prophecy.

(The part of Batman in tonight's performance was played by Robert.)