Freepers aren't going to like it, but only McCain could stop her, although I think she'd also beat him in a close election, in part because conservatives wouldn't turn out but mostly because the media would paint her as real likable. She'd have some of the most skilled people shaping her message, which would focus on attracting suburban Republican leaning women.
...I agree 100% with you, only McCain has the star power to oppose her...and her hold over the media might be lessensed, as the journalists fawn over him as well...a conundrum for them, surely, whom to support, whom to make king...excuse me, make that monarch, no sexist language allowed anymore...at any rate, what's the alternative, Duncan Hunter? Macaca Allen? Santorum?