Rudy could beat her, although I'd only barely want him to.
McCain? No way.
Romney? Maaa-aaa--ybe.
Newt? Probably not, and that's sad because he'd do wonders for America.
Hunter? Eeeh, if he gets some name recognition, and I mean PRONTO, it could happen.
Brownback? Pu-leeze.
Newt, who's not "running" officially, is the only conservative in the bunch you mentioned. (there's a bunch on this forum that don't want Newt, but they have NO real conservative alternative)