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Pennsylvania votes in key contest Pennsylvania votes in key contest
(30 minutes later)
Democrats in the state of Pennsylvania have begun voting in a critical battle between White House hopefuls Hillary Clinton and Barack Obama.Democrats in the state of Pennsylvania have begun voting in a critical battle between White House hopefuls Hillary Clinton and Barack Obama.
The state could be a decisive test in what has become an increasingly bitter fight for the Democratic nomination.The state could be a decisive test in what has become an increasingly bitter fight for the Democratic nomination.
While Mrs Clinton is expected to win, analysts say she needs a convincing victory, ideally with a double-digit lead, to keep her campaign alive.While Mrs Clinton is expected to win, analysts say she needs a convincing victory, ideally with a double-digit lead, to keep her campaign alive.
Two polls released on Monday showed her ahead by 10% and 7% in the state. The latest polls show her ahead by between 7% and 10% in the state.
A Suffolk University survey showed Mrs Clinton leading Mr Obama by 52% to 42%, while a Quinnipiac University poll had her on 51%, with him on 44%. A Zogby survey released on Tuesday showed Mrs Clinton leading Mr Obama by 51% to 41%, while an InsiderAdvantage poll had her on 49%, with him on 42%.
DEMOCRATIC DELEGATES Barack Obama: Pledged delegates: 1,415Super-delegates: 233Total: 1,648 Hillary Clinton: Pledged delegates: 1,251Super-delegates: 258Total: 1,509 Source: AP estimates on 22 April Q&A: US election delegatesPennsylvania voters' viewsJustin Webb's blogWagnerian dramaDEMOCRATIC DELEGATES Barack Obama: Pledged delegates: 1,415Super-delegates: 233Total: 1,648 Hillary Clinton: Pledged delegates: 1,251Super-delegates: 258Total: 1,509 Source: AP estimates on 22 April Q&A: US election delegatesPennsylvania voters' viewsJustin Webb's blogWagnerian drama
Polling stations opened at 0700 (1100 GMT), with results expected soon after they close at 2000 (0000 GMT).Polling stations opened at 0700 (1100 GMT), with results expected soon after they close at 2000 (0000 GMT).
With four million registered Democrats, and 158 pledged delegates to the Democratic Party's nominating convention in August, Pennsylvania is the last of the big states to hold a primary.With four million registered Democrats, and 158 pledged delegates to the Democratic Party's nominating convention in August, Pennsylvania is the last of the big states to hold a primary.
Although Mrs Clinton is behind in the delegate count and in the total votes cast, she has won most of the big state contests.Although Mrs Clinton is behind in the delegate count and in the total votes cast, she has won most of the big state contests.
And the white working class voters who have formed the backbone of her support so far are a significant constituency in the state.And the white working class voters who have formed the backbone of her support so far are a significant constituency in the state.
With the delegates split in proportion with the vote, neither candidate is expected to win sufficient pledged delegates to seal the nomination in the remaining primaries, and the two are courting 800 or so unelected "super-delegates".With the delegates split in proportion with the vote, neither candidate is expected to win sufficient pledged delegates to seal the nomination in the remaining primaries, and the two are courting 800 or so unelected "super-delegates".
Mr Obama leads nationally, but is trailing in PennsylvaniaMr Obama leads nationally, but is trailing in Pennsylvania
Pennsylvania provides a key test for Mrs Clinton's argument - which she hopes will sway the super-delegates - that only she will be able to secure wins in critical large states come November's presidential election.Pennsylvania provides a key test for Mrs Clinton's argument - which she hopes will sway the super-delegates - that only she will be able to secure wins in critical large states come November's presidential election.
The BBC's North America editor, Justin Webb, says the state's voters have the power to keep Mrs Clinton's White House dream alive by giving her a substantial victory, to do it further damage by delivering a close result, or to destroy it by handing a win to Mr Obama.The BBC's North America editor, Justin Webb, says the state's voters have the power to keep Mrs Clinton's White House dream alive by giving her a substantial victory, to do it further damage by delivering a close result, or to destroy it by handing a win to Mr Obama.
'Politics of fear''Politics of fear'
On a TV talk show on Tuesday morning, Mrs Clinton predicted victory but insisted that the margin did not matter. Instead, she said, if Mr Obama failed to win it would call into question "his ability to win the big states".On a TV talk show on Tuesday morning, Mrs Clinton predicted victory but insisted that the margin did not matter. Instead, she said, if Mr Obama failed to win it would call into question "his ability to win the big states".
Voters in Philadelphia voice their views on Barack Obama and Hillary ClintonVoters in Philadelphia voice their views on Barack Obama and Hillary Clinton
Mr Obama conceded that his rival "has to be heavily favoured to win" in Pennsylvania, but dismissed the big-state argument, saying there was "no chance" of the Democrats losing New York or California in the presidential election, no matter who the candidate was.Mr Obama conceded that his rival "has to be heavily favoured to win" in Pennsylvania, but dismissed the big-state argument, saying there was "no chance" of the Democrats losing New York or California in the presidential election, no matter who the candidate was.
Last-minute campaigning was marked by a row about Mrs Clinton's latest campaign advert.Last-minute campaigning was marked by a row about Mrs Clinton's latest campaign advert.
In the hours before the polling stations opened, Mrs Clinton was accused of trading in the "politics of fear".In the hours before the polling stations opened, Mrs Clinton was accused of trading in the "politics of fear".
Her final campaign advert featured shots of historic world events such as Pearl Harbour and the fall of the Berlin Wall, with clips of al-Qaeda leader Osama Bin Laden and Hurricane Katrina victims.Her final campaign advert featured shots of historic world events such as Pearl Harbour and the fall of the Berlin Wall, with clips of al-Qaeda leader Osama Bin Laden and Hurricane Katrina victims.
The advert concluded with the line: "You need to be ready for anything."The advert concluded with the line: "You need to be ready for anything."
Mrs Clinton's chief strategist Geoff Garin said it was a positive advert.Mrs Clinton's chief strategist Geoff Garin said it was a positive advert.
"It states why Hillary Clinton is the right choice to be president," he said. "We're at a moment where we need a president who's got the strength and knowledge to take on very tough challenges.""It states why Hillary Clinton is the right choice to be president," he said. "We're at a moment where we need a president who's got the strength and knowledge to take on very tough challenges."
But Bill Burton, from Mr Obama's team, said: "We already have a president who plays the politics of fear, and we don't need another."But Bill Burton, from Mr Obama's team, said: "We already have a president who plays the politics of fear, and we don't need another."
There has been increasing pressure from senior Democrats for a swift resolution to the deadlock between the candidates, fearing the drawn-out battle will damage the eventual candidate's prospects of success against Republican John McCain.There has been increasing pressure from senior Democrats for a swift resolution to the deadlock between the candidates, fearing the drawn-out battle will damage the eventual candidate's prospects of success against Republican John McCain.
Mr Obama has spent heavily in Pennsylvania - he had a $42m (£21m) war chest for April while Mrs Clinton had $9m - and some analysts say he is polling better in the state's urban areas than rural ones.Mr Obama has spent heavily in Pennsylvania - he had a $42m (£21m) war chest for April while Mrs Clinton had $9m - and some analysts say he is polling better in the state's urban areas than rural ones.