The personal is not political.
The closest you can get to having a guy's back in this situation is to say he messed up but shouldn't be judged in the public sphere. It's especially useful when your own past is speckled, and when you've put the canoodler in a position of trust: former presidential candidate Rudy Giuliani stuck up for his Southern campaign chairman, Sen. David Vitter, while artfully salvaging his own reputation. "I believe that this is a personal issue," he said, and went on to say that most of those he appointed were "outstanding people." In justifying his vote to acquit President Clinton, Sen. Evan Bayh kicked the moral matter upstairs. "Ultimately, he will be judged for his sins by that tribunal before which we all must stand one day," he said. "But we must apply a mortal, constitutional standard here." The heavenly retribution strategy hits on two fronts, pleasing the religious base while freeing you from the risk of actually taking action.
Nothing says loyalty like blind faith in the face of inconvenient truths. Said then-Vice President Al Gore of his boss in 1998: "The president has denied the charges, and I believe it."
Make up a limerick.
Should only be used if you have nothing to lose. In 2007, John Kerry composed this gem:
There once was a man named Vitter
Who vowed that he wasn't a quitter
But with stories of women
And all of his sinnin'
He knows his career's in the—oh, never mind.
AP Video: South Carolina Gov. Mark Sanford Admits Affair