Getting caught cheating won't make any difference. In fact, the MSM will play that as a 'so what, he's cleverer than GW, hahahaha.' In fact, even if his military record became public and we found out there was something detrimental on it, such as that he'd gotten a dishonorable discharge, later cleaned up by Carter...the MSM would back him all the way. Other than being caught in the act of cold blooded murder, I can't think of anything Kerry could do that the MSM wouldn't think was swell.
I am reminded of the rules of contract bridge which stipulate that any prearranged methods of communication between partners, other than by means of legal plays, are absolutely and fundamentally cheating; if it is proven that a partnership used such methods, the cheaters are permanently ineligible for all ACBL events. Not some "unsportsmanlike conduct" penalty--permanent expulsion.
There are some types of conduct where people are expected to try to skirt the rules a little here and there and see if they can get away with it. But there are other events where rules are supposed to be followed, and where pushing them isn't the conduct of a crafty Han Solo, but is instead the conduct of a cheater. Some people don't understand the distinction.