Pennsylvania Primaries (19 images)

Democratic Presidential candidate Sen. Hillary Clinton (D-NY) acknowledges the crowd at a victory rally after winning the Pennsylvania presidential primary in Philadelphia on April 22, 2008. (UPI Photo/Kevin Dietsch)

Supporters of Democratic Presidential candidate Hillary Clinton reacts after it was announced that Clinton is projected to win the Pennsylvania Presidential Primary in Philadelphia on April 22, 2008. (UPI Photo/Kevin Dietsch)

Democratic Presidential candidate Sen. Hillary Clinton (D-NY) stands for an ovation alongside her husband former President Bill Clinton at a victory rally after winning the Pennsylvania presidential primary in Philadelphia on April 22, 2008. (UPI Photo/Kevin Dietsch)

Democratic presidential hopeful Sen. Barack Obama waves the Pittsburgh Steelers "Terrible Towel" outside of the P&G Pamela's Diner, in the Strip District section of Pittsburgh, a restaurant well known for their crepe style pancakes on the morning of the Pennsylvania Primary election April 22, 2008. (UPI Photo/Archie Carpenter)