I f you happen to find yourself listening to Conversation 62 of Tape 33 of the new Nixon documents released this summer, this is what you will hear: On Election Night 1972, Richard M. Nixon, having served George McGovern the biggest electoral college defeat in history, took a congratulatory phone call from Hubert H. Humphrey, who all but admitted he had wanted McGovern to lose, and that he had tried to keep him from winning...