WASHINGTON, March 16 (UPI) -- There is growing concern among U.S. Democratic leaders that there could be a protracted battle for the party's presidential nomination, a report said Sunday.

Superdelegates, the roughly 700 party insiders and elected officials who will weigh in on who should be at the top of the Democratic ticket, are divided on how to resolve the tight contest between Sens. Hillary Clinton and Barack Obama, The New York Times (NYSE:NYT) reported.

Although Obama, of Illinois, has won more delegates in the state-by-state contests, Clinton, of New York, leads in the number of superdelegates pledged to her, the newspaper said.

"If we get to the end and Senator Obama has won more states, has more delegates and more popular vote, I would need some sort of rationale for why at that point any superdelegate would go the other way, seeing that the people have spoken," said Rep. Jason Altmire, D-Pa., an undecided superdelegate.

Other superdelegates expressed concern that the protracted race could hurt Democrats' chances in the general election against Sen. John McCain, R-Ariz.

"It would be nice to find a way to wrap it up," said Rep. Chris Van Hollen of Maryland, chairman of the Democratic Congressional Campaign Committee and an uncommitted superdelegate.

"If the current trajectory of the debate continues, the divisions will make it more difficult for many of our candidates," he said.