A pre-talk show Jerry Springer, during his unsuccessful 1982 Ohio gubernatorial campaign, admits to Spitzer-esque indiscretion:

Rule of Thumb: Any mea culpa that includes the phrase ??nd I paid her with a check?is problematic in politics.

(I concede that phrase may have more to do with the facts of this particular situation than the advertising created to address it. Nevertheless! Candidates, consider yourselves warned.)