Pennsylvania Democrats cast White House votes

Hillary Clinton was hoping for a convincing win to keep her flickering White House hopes alive yesterday as Pennsylvania Democrats chose between her and Barack Obama in their presidential nominating contest. Polls closed at 8 p.m. EDT (0000 GMT) with results expected shortly thereafter.

The New York senator is favoured in Pennsylvania but needs a substantial victory to gain ground on Mr Obama in the Democratic race and convince party leaders she is the best candidate to face Republican John McCain in November's presidential election.

Mrs Clinton's one-time 20-point lead in the state has slipped to single digits in many polls amid an onslaught of advertisements by Mr Obama, who has heavily outspent her in the first nominating contest in six weeks. Both camps tried to play down expectations ahead of the vote.

"I'm not predicting a win. I'm predicting it's going to be close and that we are going to do a lot better than people expect," Mr Obama told a Pittsburgh radio station on Monday. The two candidates spent the final day of an increasingly sharp fight scouring the state for last-minute support. Mrs Clinton released an ad featuring images of al Qaeda leader Osama bin Laden and touting her strength.

"You need to be ready for anything - especially now, with two wars, oil prices skyrocketing and an economy in crisis," the ad's narrator says. "Who do you think has what it takes?"

Mr Obama's camp accused her of using "the politics of fear" and he released an ad in response. "Who in times of challenge will unite us - not use fear and calculation to divide us?" the ad asked.

The Pennsylvania vote opens the final phase of Mrs Clinton and Mr Obama's hard-fought duel for the nomination. Nine more contests are scheduled before the campaign concludes on June 3.

Mr Obama has a nearly insurmountable lead in popular votes won during the first three months of the primary battle and in delegates who will choose the nominee at the August convention. But neither can clinch the nomination without the help of super-delegates - nearly 800 party insiders who are free to support either candidate.