The only Democrat that has been mentioned here who was found out while in office was President Clinton. Had he bowed out, he would have acted against the wishes of the majority of his constituency, who knew that the mob action being waged against him by the Republicans was a defacto Coup d'Etat.

None of the Republicans who bowed out did so prior to their misdeeds being exposed to the public. They bowed out because their party told them to. Had integrigy or moral uprightness been an issue for them, A. they wouldn't have done the deeds in the first place, and B. they would have bowed out immediately, rather than waitng to be found out before doing so.