Appearing on CBS's "Face the Nation," the Democratic Party head said either U.S. Sen. Hillary Clinton, D-N.Y., or Sen. Barack Obama, D-Ill., must be established as the party's presidential nominee prior to the August convention or the party will suffer.

"If it goes on -- if you go into the convention divided, you're probably going to come out of the convention divided," he said of the ongoing party turmoil.

Dean also said the remaining superdelegates should decide on which candidate they are going to support to help the Democratic Party and the country prepare for the general election campaign against Sen. John McCain of Arizona, the presumptive Republican nominee.

"So I think the remaining 300-and-some-odd superdelegates or unpledged delegates will continue to do what the 470-odd have already done, which is to make their views know in drips and drabs between now and the end of June," he said. "And I think that's the right thing to do for the country, never mind just the party."