by KYW's Larry Kane

History sometimes plays a major role in political endorsements, and it did on Friday when Sen. Bob Casey (D-Pa.) endorsed Barack Obama in Western Pennsylvania -- an important endorsement for Obama in the state.
    
Appearing on stage beside the Illinois senator in Pittsburgh, Casey told a boisterous rally, "I believe in my heart that there is one person who's uniquely qualified to lead us in that new direction and that is Barack Obama."
    
His support could help Obama make inroads among Catholic voters, who have preferred Clinton to Obama in earlier primaries and strongly favor her in Pennsylvania polls.
    
"I really believe that in a time of danger around the world and in division here at home, Barack Obama can lead us, he can heal us, he can help rebuild America," he said.
    
Obama told the crowd that he had not pushed Casey hard for an endorsement:

"Bob is such a gracious person and such a thoughtful person that I did not press him on this endorsement," especially since Obama trails Clinton in Pennsylvania polls.
    
"It would have been easy for Bob just to stay out of it, just to stay neutral, I think everybody would have accepted that," Obama said.
    
Casey said that he called Clinton on Thursday night to tell her of his decision:
    
"She was very gracious. We know that she's a great senator, she's a great leader."

Pennsylvania's April 22nd primary will allocate 158 delegates, the biggest single prize left in the drawn-out nomination battle between Obama and Sen. Hillary Rodham Clinton of New York. Clinton is leading Obama in the state, by 12 points in one poll this month.
    
Casey is a first-term senator and the son of a popular former governor of the state. Casey is Catholic and, like his father, is known for his opposition to abortion and support of gun rights. 

The Casey endorsement came as Obama began a six-day campaign swing through Pennsylvania.

Obama's team hopes that Casey will help narrow Clinton's huge lead among white working-class voters -- men in particular. Clinton routed Obama among that demographic in Ohio and Texas on March 4th, raising questions about his electability in November. In recent weeks, Obama has stressed economic issues important to the middle class, and he is outspending Clinton on television advertising that features blue-collar imagery.
    
Casey had a 62 percent approval rating among Democrats in a recent Quinnipiac University poll. Casey was to campaign with Obama as he travels across Pennsylvania by bus.
    
The bus tour will feature "listening sessions," a technique Clinton used in her 2000 Senate campaign to convince skeptical New Yorkers that she was not just a carpetbagger looking for a plum post after leaving the White House.
    
Obama hopes to prevent Clinton from racking up a large win in the state which could eat away at his delegate advantage and give her new life in the final primaries running to June.
    
It may be a tough sell for some in the state, which has a sizable elderly population. In the previous primaries, older Democrats have favored Clinton, while younger voters tend toward Obama.
    
Casey served two four-year terms as state auditor general. He lost a 2002 gubernatorial bid in the Democratic primary to Rendell. Casey was elected to the Senate in 2006, defeating conservative GOP incumbent Rick Santorum. Obama campaigned for Casey, but so did Clinton and her husband.
  
There's no question that in the last several years a true alliance has been formed between Casey and Obama; they are friends on the US Senate floor and in Washington. 
  
But there's an inside story of what happened here, and it goes back to 1992.

The late Robert Patrick Casey, governor of Pennsylvania at the time, asked for a few moments from the Clinton forces to speak at the Democratic National Convention in New York City about his pro-life views. He wanted to show that there were other views on abortion in the Democratic Party.

He was denied that access despite pleas from James Carville and Sen. Harris Wofford. Casey -- father of the current senator -- was bitter and angry, and he carried that bitterness to his death as he forged ahead with his pro-life views across the country.

That was never forgotten by the Casey family, and you could say that this endorsement is somewhat of a payback politically --  but also a sincere endorsement on the part of the younger Bob Casey. 
    
Meantime, a leading Obama backer, Sen. Patrick Leahy (D-Vt.) is saying Clinton should abandon her White House run:
    
"There is no way that Sen. Clinton is going to win enough delegates to get the nomination," Leahy told Vermont Public Radio in an interview that aired Thursday.
    
In a statement issued Friday, Leahy, the Senate Judiciary Committee chairman who endorsed Obama in January, said Casey's endorsement of Obama is the latest sign of how the race is going:
    
"Sen. Clinton has every right, but not a very good reason, to remain a candidate for as long as she wants to. As far as the delegate count and the interests of a Democratic victory in November go, there is not a very good reason for drawing this out. But as I have said before, that is a decision that only she can make."
 
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