I’m curious – hasn’t the latest call of the Obama folks been that superdelegates ought to support the will of their given constituencies? If so, does this mean a switch to Hillary at the convention by Senator Bob Casey?

Pennsylvania Sen. Bob Casey 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.

Dan Pfeiffer, deputy communications director for the Obama campaign, confirmed that Casey would announce his support during a rally at the Soldiers and Sailors Military Museum and Memorial and that he would then set out with the Illinois senator on part of a six-day bus trip across the state.

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.

"There are few stronger advocates for working families in Pennsylvania than Sen. Casey," Pfeiffer said.

By coming out for Obama, Casey puts himself at odds with many top state Democrats - including Gov. Rendell, Rep. John P. Murtha and Mayor Nutter - who are campaigning for Clinton.

Now polling data shows that Obama is going to take a real drubbing in Pennsylvania. Doesn’t that mean that the Obama campaign should have rejected Casey’s help – you know, in the interest of guaranteeing that the Pennsylvania senator doesn’t go against the will of Pennsylvania voters?

Or are their protestations about respecting the vote of the people simply more lip service to principle while hypocritically doing anything to win?