Good question jno (as usual, by the way. Fact is, over the last few year 'family values' has become nothing more than a catch phrase. Ot of the current batch of possible nominees, the Republican's winner last night in Iowa, Mike Huckabee isn't divorced, Mitt Romney isn't, Rudy Giuliani is (twice, once very messy), and John McCain isn't. Amongthe Democrats, Hillary isn't, but that truly is seen as a political calculation since there doesn't seem to be much of substance to the marriage anyway, except political calculation, the winner Barack Obama isn't and John Edwards isn't (in fact his wife is suffering from cancer, outlook unknown).
But, the appeal of a clean cut, family oriented, mildly but not blatantly religious (which makes Huckabee a real question mark for the long run) experienced but not part of the system has great appeal to a lot of the electorate. Unfortunately, the party faithful will almost always choose adherence to the dogma over a good candidate everytime. Especially after the press and the various party "machines" get through dredging up every possible negative factor of the opposing candidates life... which a lot of people tend to feed on... tsk, tsk... rant over...