Pennsylvania Primaries (19 images)

Michele Obama, wife of Democratic presidential hopeful Sen. Barack Obama address supporters attending the rally at the Peterson Event Center in Pittsburgh on April 21, 2008, the eve of the Pennsylvania Primary election. (UPI Photo/Archie Carpenter)

Democratic presidential hopeful Sen. Barack Obama shakes hands 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)

Democratic Presidential candidate Sen. Hillary Clinton (D-NY) waves to supporters as her husband former President Bill Clinton follows behind as she makes her way to the stage after winning the Pennsylvania Presidential Primary during a rally in Philadelphia on April 22, 2008. (UPI Photo/Kevin Dietsch)