09/04/2009 05:12 am ET Updated Dec 06, 2017

Pennsylvania Senate Battle Heats Up: Top Candidates Hammer Away At Each Other

Sen. Arlen Specter (D-Penn.) and his two major senate challengers in 2010, Rep. Pat Toomey (R-Penn.) and Rep Joe Sestak (D-Penn.), all hammered away at each other on Tuesday while speaking to Chris Matthews, a Pennsylvania native.

Toomey, the Republican challenger, repeatedly blasted Specter as a political opportunist with no core ideals. Toomey alleged that "the only principle that's important to Arlen Specter is his own reelection," seizing on Specter's recent switch to the Democratic party after 28 years as a Republican senator.

"This is a guy who has made a career out of being on both sides of as many issues as he can," said Toomey.

Toomey described himself as politically "in the center-right," and "a supporter of limited government, less government spending, ending the bailouts, lower taxes, free enterprise." He also said he was "pro-life" and believed states should be allowed to outlaw abortion. He dismissed the "birther" viewpoint.

Specter's sights were set on the Democratic primary, as he focused his attacks on Sestak. Specter slammed Sestak's voting record, saying "he's missed 105 votes" and had the "worst record" of any Pennsylvania Congressman. In a series of tweets posted hours before his appearance on Hardball, Specter called into question Sestak's competence, his work ethic and his integrity.

But Specter also said of Sestak: "I think he's a fine Congressman and ought to stay in the House of Representatives," before defending his own legislative record on jobs, health care, education and the environment.

Grilled on his decision to switch parties, Specter responded that he believed the Republican party had become too ideologically intense for him. "[My] effort to bring moderation to the Republican party was not successful," he said, adding "I feel very comfortable as a Democrat."

Specter touted his endorsements from President Obama and Vice President Biden, and admitted that his support for Republicans McCain and Palin in 2008 was a political decision, and not one based on conviction: "When you're in a party and you work for a party and you're trying to work within the structure to moderate the party, I think that's the correct thing to do," he said.

Sestak, who officially announced Tuesday that he will challenge Specter in the Democratic primary next year, dismissed Specter's allegations. "I don't know" what he's talking about, said Sestak, "and I really don't." Sestak went on to defend his record, particularly with middle-income Pennsylvanians and had harsh words for top leaders in Washington.

"Washington never kept the middle-class, the working families in mind," said Sestak. "That's why I'm running."

A recent poll involving a potential battle between Specter and Toomey showed the two at a statistical dead heat. Another poll conducted late in May found Specter comfortably leading Sestak in a potential primary.

WATCH Toomey:

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