"...and of course President Garfield was shot in July..."

(CNN) -- Former President Bill Clinton said that Democrats were more likely to lose in November if Hillary Clinton is not the nominee, and suggested some were trying to "push and pressure and bully" superdelegates to make up their minds prematurely.

Bill Clinton did not explain who he was accusing of "covering up" Sen. Clinton's chances.

"I can't believe it. It is just frantic the way they are trying to push and pressure and bully all these superdelegates to come out," Clinton said at a South Dakota campaign stop Sunday, in remarks first reported by ABC News.

Clinton also suggested some were trying to "cover up" Sen. Clinton's chances of winning in key states that Democrats will have to win in the general election.

" 'Oh, this is so terrible: The people they want her. Oh, this is so terrible: She is winning the general election, and he is not. Oh my goodness, we have to cover this up.' "

Clinton did not expound on who he was accusing. Watch Clinton talk about the "cover up." »

The former president added that his wife had not been given the respect she deserved as a legitimate presidential candidate.

"She is winning the general election today and he is not, according to all the evidence," Clinton said. "And I have never seen anything like it. I have never seen a candidate treated so disrespectfully just for running."

"Her only position was, 'Look, if I lose I'll be a good team player. We will all try to win, but let's let everybody vote, and count every vote,' " he said.

The former president suggested that if the New York senator ended the primary season with an edge in the popular vote, it would be a significant development.

"If you vote for her and she does well in Montana and she does well in Puerto Rico, when this is over she will be ahead in the popular vote," Clinton said.