Pennsylvania Senator Bob Casey has formally endorsed Barack Obama - a move which will be a major blow to Hillary Clinton's campaign for the nomination.
Casey is an extremely popular Democrat in Pennsylvania, and his support will go a long way to making inroads into the white, conservative voters in that state. This is Obama's first major endorsement in Pennsylvania.
Pennsylvania Democrats go to the polls on April 22. Hillary Clinton still enjoys a solid double digit lead in that state, but a strong win there is crucial for her to stay in the race.
Obama is commercing a 6 day tour of the state, where he hopes to narrow Clinton's lead.
The Obama endorsement by Casey, the son of a former popular Governor, has ended a bad week for Clinton. Two national polls have shown her trailing Obama, she has had to defend her statements on her trip to the Balkans, and Gov. Richardson has also endorsed Obama.
Obama Secures Key Endorsement
