Sen. Bob Casey (D-PA) plans to endorse Sen. Barack Obama for president today in Pittsburgh, "sending a message both to the state's primary voters and to undecided superdelegates who might decide the close race for the Democratic presidential nomination," according to the Philadelphia Inquirer.
"The endorsement comes as something of a surprise. Casey, a deliberative and cautious politician, had been adamant about remaining neutral until after the April 22 primary. He had said he wanted to help unify the party after the intensifying fight between Obama and Sen. Hillary Rodham Clinton."
"The endorsement also comes at a crucial time for Obama, who has been trailing Clinton in Pennsylvania polls by double-digit margins but who also has bought at least $1.6 million worth of television advertising statewide in the last week, more than double Clinton's expenditure."