Massachusetts Sen. John Kerry on Monday endorsed Republican-turned-Democrat Arlen Specter in Pennsylvania's contested Senate primary as the incumbent tries to fend off criticism that he used "Swiftboat"-style attacks.
The 2004 Democratic presidential nominee released a statement praising Specter as a "fighter and a friend, and I am proud to vouch for his character." Kerry's press secretary, Whitney Smith, later said Kerry was endorsing Specter.
Specter is in a close race with Rep. Joe Sestak for the Democratic nomination. Specter raised questions about Sestak's Navy record and the retired Navy admiral accused his rival of a "Swift Boat"-style attack.
In 2004, Swiftboat Veterans for Truth made unsubstantiated claims about Kerry's Navy record during the Vietnam War.
In his statement Monday, Kerry said he didn't want to referee a Swiftboat fight but did want to defend Specter's record.
"That's an issue for the candidates to address and the media to investigate," Kerry said. "However, as the political season turns increasingly heated, I want to insist on a reality check about my colleague, Arlen Specter. I have known Arlen for 25 years and I know his character and the quality of his service to Pennsylvania."
Kerry said he is friends with both candidates, and had been an early backer of Sestak's 2006 House campaign.
"I've been reluctant to get involved in a primary between two friends, and even more reluctant to be drawn into arbitrating the definition of the term Swiftboating," Kerry said. "I'd like to see us get to a better place in politics where the word Swiftboating is retired from the political vocabulary."
President Barack Obama also is backing Specter, who is seeking a sixth term. Specter switched parties in April 2009 as it looked unlikely he could capture the GOP nomination against conservative challenger Pat Toomey.
Recent polls show a close race. The primary is May 18.
Chris Nicholas, Specter's campaign manager, said the senator is grateful for Kerry's support.