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Democrat voters in Pennsylvania have till 8 p.m. local time (midnight (GMT+2) Paris time) to choose their candidate for the presidential elections in November. The event is critical for Hillary Clinton, who needs to win big if she is to stay in the race.
A defeat for Clinton, who lags behind rival Barack Obama in delegate votes, would force an end to her campaign, even though she stated the contrary Monday on CNN.

However, the New York senator is tipped to win in Pennsylvania, a state badly affected by the economic crisis. According to an April 20 survey by the University of Suffolk, 52% of voters intend to vote for the former first lady, as opposed to 42% for the Illinois senator.

Clinton needs a significant lead

“It is highly probable that she will win the primary, but by how much – there lies the question,” said Frederick T. Davis of the French American Foundation in Paris on France 24's FACE-OFF. “She should get a lead of 10 points,” suggested Meredith Gowan Le Goff of the Council of Democrats Abroad .

Since a televised debate on ABC, followed by more than 10 million spectators, Clinton has been faring well in surveys. She attacked Obama for his links to the controversial pastor Jeremiah Wright, who was accused of preaching anti-American sermons. Clinton also criticised her rival's remarks about  “bitter" small towns of Pennsylvania, where residents “cling to guns or religion…”.

Obama is not conceding defeat as yet. He deployed 9.3 million dollars in television advertisements in Pennsylvania, dwarfing Clinton's campaign budget of 3.2 million dollars.

158 delegates to share

The former first lady needs a significant lead in the Pennsylvania primary to win the Democratic nomination. 158 delegates are up for grabs. If the two candidates are separated by a narrow margin (around 5%), each will be credited with almost the same number of votes. In 2004, John Kerry won the primary in Pennsylvania, nicknamed the “Keystone State.”

Obama has won more states than his rival (28 against 14). He also has more delegates to his name (1650 against 1508) and has bagged more votes (13.3 million against 12.6 million).

Nine more primaries are to be held till June 3. The next will take place May 6 in Indiana and North Carolina.