05/30/2009 05:12 am ET Updated May 25, 2011

Obama Welcomes Specter To Party At White House

President Obama and Vice President Biden joined former Republican Senator Arlen Specter at a press conference on Wednesday morning, welcoming him to the Democratic party.

Biden introduced the Pennsylvania senator, saying it gave him "great pleasure to officially be in the same caucus as Arlen Specter ... it's just a delight."

Specter pronounced himself "ready willing and anxious to take on all comers in the general election" and restated that he would not be an "automatic sixtieth vote" for Senate Democrats. But he told Obama he thought he could "be of assistance to you" and that "you have projected an administration that I have felt very comfortable with."

On Tuesday, President Obama called Specter to tell him "you have my full support" and we are "thrilled to have you," according to a White House aide.

"Thank you so much," Obama said. "I'm thrilled to have Arlen in the Democratic caucus, I have told him he will have my full support in the Democratic primary." He said he and Biden were fully confident that Specter will win a new term, and that the people of Pennsylvania "will be better off for it."

Obama diverged briefly to speak about the swine flu crisis, addressing the first United States death as a result of the virus. The president sent his condolences to the family of the victim and urged local health agencies around the country to be vigilant and help national authorities track the disease. He also said that schools where the virus has broken out should strongly consider temporarily closing.

The president brought his remarks back to Specter, crediting him with increasing funding for public health and calling him "one tough hombre."

"Today I have the honor of standing next to the newest Democratic from the state of Pennsylvania," Obama said. "I don't expect Senator Specter will agree with every decision I make, and support every one of those policies." He said he didn't expect Specter, or any other senator, to be a "rubber stamp." He added that Specter's move reflected his vision of an administration not driven by one ideology. "I'm eager to receive his counsel and advice, especially when he disagrees, and I have great respect and admiration for the decision he has made."

Advisers told the AP that was the first Obama had heard that Specter was switching parties, though they left open the possibility that White House officials, if not Obama himself, knew in recent days that a change was possible.

Democratic officials privately credited Biden, the former Delaware senator who is close to Specter both personally and professionally, and his persistent prodding through the years with helping create a comfortable, welcoming environment for the five-term Pennsylvania senator to make the change. Obama hinted at this role himself on Wednesday, saying he was "grateful" to the Vice President for having so many conversations with Specter on the train to Washington.

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