SIOUX FALLS, S.D. – George McGovern once joked that he had wanted to run for president in the worst way – and that he had done so.

It was a campaign in 1972 dishonored by Watergate, a scandal that fully unfurled too late to knock Republican President Richard M. Nixon from his place as a commanding favorite for re-election. The South Dakota senator tried to make an issue out of the bungled attempt to wiretap the offices of the Democratic National Committee, calling Nixon the most corrupt president in history.

But the Democrat could not escape the embarrassing missteps of his own campaign. The most torturous was the selection of Missouri Sen. Thomas F. Eagleton as the vice presidential nominee and, 18 days later, following the disclosure that Eagleton had undergone electroshock therapy for depression, the decision to drop him from the ticket despite having pledged to back him “1,000 percent.”