Clinton: "Tide is turning" with Pennsylvania win

"Some people counted me out and said to drop out," Clinton said, drawing loud boos at her victory rally in Philadelphia. "But the American people don't quit, and they deserve a president who doesn't quit, either."

With more than 75 per cent of the state's precincts reporting, Clinton had 54 per cent of the vote to Obama's 46 per cent.

Even with the win, the former first lady is unlikely to make significant inroads into Obama's lead in delegates to the party's August nominating convention, which has prompted some to call for her to exit the race.

Clinton said the Pennsylvania victory gave her strong momentum heading into the remaining nine contests.

"You made your voices heard, and because of you the tide is turning," she said. "It's a long road to (the White House), and it runs right through the heart of Pennsylvania."

Clinton made an impassioned plea to her supporters for campaign donations, after being vastly outspent by Obama in Pennsylvania in the last six weeks of campaigning.

Obama took in 40 million dollars in March - twice as much as Clinton - and a spokesman for her campaign Monday admitted she was nearly 10 million dollars in debt.

"We can only keep winning if we can keep competing with an opponent who outspends us so massively," Clinton said, telling supporters to give money through her website.

With more than 50 per cent of precincts reporting, Clinton had 55 per cent to Obama's 45 per cent as the former first lady battles to keep her White House bid alive.

Obama holds the lead in delegates to the party's nominating convention in August, and analysts had said Clinton needed a significant win to gain momentum for the nine remaining intra-party contests and stave off demands that she step aside.

Obama, 46, admitted Monday that he expected a Clinton victory in the state, but Clinton, 60, has said that any win would be significant after six weeks of tireless and increasingly negative campaigning.

Clinton's edge of as much as 20 points several weeks ago had been whittled to as little as 5 per centage points by Obama, who has outspent her on advertising by more than two-to-one in Pennsylvania.

Voters turned out in droves across the state Tuesday, with the economy and health care on their minds and the fate of Clinton's presidential ambitions in their hands.

Nationally, Obama has a small lead of 150 delegates in the race to the Democratic nominating convention in August, where 2,024 delegates are needed to reach a majority.

Pennsylvania had 158 delegates are up for grabs Tuesday and only about 500 are left in the remaining nine contests. Indiana and North Carolina are next on May 6.

Even if Clinton fell short of a significant win in Pennsylvania, the New York senator had indicated that she won't back down, and her stance was welcomed by her supporters at a polling station in Hershey, Pennsylvania.

"Sometimes we've got to go through pain to gain, and if it's for the right person to be the nominee, it's absolutely necessary," said Suzanne Brinser, 40, after voting for Clinton.//dpa