In the U.S. presidential race, a growing number of Democrats are worried that the long and bitter nomination fight between Senators Barack Obama and Hillary Clinton may be helping the presumptive Republican candidate, Senator John McCain.  VOA National correspondent Jim Malone has more on the strains within the Democratic Party from Washington.

Some Democrats, many of them Obama supporters, argue there is no way that Hillary Clinton can overtake Barack Obama in the delegate count, and they want her to step aside for the good of the party.

But out on the campaign trail, Hillary Clinton says voters are telling her just the opposite.

"The most common thing that people say to me, it happened here, it happened last night, it happens everywhere now, is do not give up," she said.  "Keep going.  We are with you."

Obama leads Clinton in the delegate count by more than 100.  Most political experts give Clinton little chance of pulling ahead of Obama in the remaining primaries and caucuses because Democrats award delegates on a proportional basis, making it difficult for challengers to make up ground on the delegate leader.

Clinton is favored in the next primary in Pennsylvania.  But Obama remains confident that he will win his share of the remaining 10 nominating contests that run into June and will emerge victorious at the Democrat's national nominating convention in August.

"We will win this nomination, we will win the general election, and, you and I together, we will change this country and we will change the world," he said.

New polls suggest the lengthy and increasingly bitter Democratic nomination fight could hurt the party in the November election.

An NBC News-Wall Street Journal poll has Obama and Clinton tied at 45 percent in a national survey, but also showed a spike in negative views of Senator Clinton.  Of those asked, 48 percent had a negative view of Clinton, compared to 37 percent who see her favorably.  Obama's numbers were 49 percent positive and 32 percent negative.

In addition, a new Gallup poll suggests the presumptive Republican nominee, Senator John McCain, is reaping benefits from the Democrat's infighting.

A total of 19 percent of Obama supporters said they would vote for McCain if Clinton were the Democratic nominee, while 28 percent of Clinton supporters said they would defect to McCain if Obama wins the nomination.

Most political analysts believe that the only way Clinton can win the Democratic nomination is for her to continue to attack Obama in the months to come and hope for support from so called super delegates, uncommitted office holders and party activists who will vote at the convention.

But experts warn that would likely rip the Democratic Party apart.

Norm Ornstein is a longtime political scholar at the American Enterprise Institute.

"So, for Mrs. Clinton, to get to the end of this nominating process if she is behind in elected delegates, overall delegates, popular votes cast nationwide and states, it is hard to imagine a Democratic Party that would nominate her under those circumstances because that would be a genuinely Pyrrhic [costly] victory," he explained.

Some of the super delegates want to prevent the Obama-Clinton battle from continuing all the way to the convention in August.

Tennessee Governor Phil Bredesen is an uncommitted super delegate.  Bredesen has proposed that the Democratic super delegates who have yet to commit to a candidate meet in June to settle the fight once and for all.

"If we go on through the summer with all these things happening behind the scenes, I think it is a terrible image for the party," he said.  "Part of the idea of doing it in a public way in June is let us get them together, let us have them listen to the candidates, let us have them publicly declare where they are and let us get out of that backroom mode."

Both Clinton and Obama have had to deal with potentially damaging controversies in recent days.

Clinton acknowledged that she misspoke when she exaggerated the dangers of a trip to Bosnia as First Lady in 1996.

Obama sought to distance himself from the racial and anti-American statements of his former pastor, the Reverend Jeremiah Wright.

New polls suggest Obama's speech on race dealing with Wright last week may have limited damage in the short term.  But many Republican strategists believe Wright will be a liability for Obama if he faces McCain in the general election.

Weekly Standard editor Fred Barnes is a frequent guest on VOA's Issues in the News program.

Barnes says some Republicans now believe Obama would be a weaker opponent than Clinton in the general election.

"They have always assumed up until very recently that Hillary Clinton would be the perfect candidate for them, the Republicans, to run against, because they think she unites the Republican Party and so on," he said.  "Now with the Jeremiah Wright affair and Barack Obama, they are not so sure.  They think Obama might be an easier candidate to beat."

In terms of general election match-ups, the NBC Wall Street Journal poll shows Obama edging McCain by 44 to 42 percent, while McCain defeats Clinton by a margin of 46 to 44 percent.