My Dad was at the Naval Academy at the same time as McCain. He was in the class ahead of my father.
He said that McCain's reputation at the Academy wasn't especially good, and like Ivy League legacies, the rest of the class realized that he was there not because of outstanding grades or stellar credentials - but because of his Admiral father. He said McCain was always a cocky entitled rich kid, and acted as such.
Ironically, at graduation the man who graduates LAST is actually accorded a kind of special honor - the "anchor man". They carry him around on their shoulders like some kind of football hero. When I watched my father's graduation film, I asked why do they do that? He answered, because he JUST - MADE - IT. Everyone after him failed or went home.
Still, out of a thousand or so classmates, graduating last or fifth from the bottom is a difference without a distinction.