Sounds like George McGovern in 1972. He had picked Sen Tom Eagleton from Mo. as VP running mate. It was soon discovered that Eagleton had had serious bouts of depression, requiring electric shock therapy. The shocked Democrats had Mc Govern issue his 1000% statement. When polls showed Eagleton in overwhelming disfavor, he withdrew. Sargent Shriver took his place on the ticket. Only Mass. voted democratic in this debacle. But, Watergate soon came to light.