Democratic Party Chairman Howard Dean, hoping to avoid a divisive fight on the convention floor, weighed in on the Clinton-Obama battle Friday by calling on all party superdelegates to declare whom they support by July 1.

The 800 or so Democratic superdelegates will almost certainly decide the presidential candidate, because it's unlikely either Barack Obama or Hillary Clinton will gain enough pledged delegates in the remaining primary contests to win the 2,025 delegates needed to clinch the nomination outright.

Dean, appearing on CBS' "Early Show" Friday morning, was asked about the prospects of a vote among the superdelegates before the convention, an idea floated as a way to settle the still undecided Democratic race.

"Well, I think the superdelegates have already been weighing in. I think there's 800 of them and 450 of them have already said who they're for," Dean said. "I'd like the other 350 to say who they're on between now and the first of July so we don't have to take this into the convention."

Dean was not asked to elaborate on his remarks during the interview.

In a separate interview with The Associated Press, Dean warned against "demoralizing" Democrats with a drawn-out fistfight between Clinton and Obama.

"You do not want to demoralize the base of the Democratic Party by having the Democrats attack each other. ... Let the media and the Republicans and the talking heads on cable television attack and carry on, fulminate at the mouth. The supporters should keep their mouths shut about this stuff on both sides because that is harmful to the potential victory of a Democrat," Dean told the AP.

Dean's comments follow an increasingly bitter and widening battle over the Democratic nomination. On Thursday, the deep-pocketed liberal organization MoveOn jumped into the fray, calling on its members to sign a petition rebuking a group of Clinton fund-raisers.

MoveOn's action was prompted when the Clinton supporters sent a letter to House Speaker Nancy Pelosi, threatening to dial back their gift-giving if Pelosi maintains her position that superdelegates should follow the will of primary and caucus voters.

The Clinton campaign and its supporters -- seeking to gain an edge in superdelegates -- have argued that superdelegates are not bound by primary voting trends and were established under party rules to be independent.

Pelosi did not back down Thursday.

Pelosi spokesman Brendan Daly said Pelosi "believes it would do great harm to the Democratic Party if superdelegates are perceived to overturn the will of the voters. This has been her position throughout this primary season, regardless of who was ahead at any particular point in delegates or votes.

Democrats also are battling over how to handle the delegations from Michigan and Florida. The party stripped the two states of their delegates to the convention when they decided to hold their primaries before party rules allowed.