Jim Webb, the freshman Senator from Virginia, never fought professionally but, while a student at the Naval Academy, did fight in an epic bout against rival midshipman Oliver North for the brigade boxing championship. The best account of which is in Robert Timburg's A Nightingale's Song.
Going into the match, Webb was considered the far superior fighter, so much so that the boxing coach was giving North extra time for fear that Webb might literally kill him. (There were rumors that North had a metal plate in his head and that one blow from Webb might knock him permanently unconscious.) But when fight time rolled around, those fears were far from realized and probably even worked against Webb:
"On fight night, contrary to Coach Smith's words, Webb was not ready. He found himself in a classic no-win situation. If he beat North everyone would say, 'Way to go, champ, you beat a cripple.' If he lost, humiliation. As Webb well realized, a crucial point was neglected in that equation. Whatever his handicaps, real or trumped up, North had fought and won enough times to get to the championship match. He was no pushover even if Webb had been at the top of his game, which he was not."
North upset Webb in a win by decision, and since both have reached some measure of Beltway fame, the fight has taken on mythic qualities within Academy circles.