Washington (CNN) – Sen. John Kerry, D-Massachusetts, used his endorsement Monday of Sen. Arlen Specter, D-Pennsylvania, to call for the retirement of the term "swift boat" from the political lexicon.
After Kerry's office released a statement praising Specter, who switched from the Republican Party a year ago, Kerry Press Secretary Whitney Smith confirmed to CNN that the Massachusetts Democrat was endorsing Specter.
"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 in a statement.
But Kerry also said that he would not serve as referee in a hostile Democratic primary battle in which the term "swift boat" has once again become an issue.
The Pennsylvania primary race between incumbent Sen. Arlen Specter and challenger Rep. Joe Sestak has become increasingly bitter in recent weeks, with both candidates slinging accusations as Election Day approaches. But Kerry's statement is likely a reference to the fallout from a political ad released in April, in which Specter questions Sestak's military record.
The Specter ad alleged that Sestak, a former three-star Navy Admiral, was "relieved of duty in the Navy for creating a poor command climate," a charge that in turn caused Sestak to accuse Specter of employing "swift boat" tactics.
The accusations have prompted Kerry, who was the target of the initial "swift boat" salvo during the 2004 presidential campaign, to weigh in on the race.
"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 in his statement.
But the carefully worded statement does not push back against Specter's original ad, or refer directly to Sestak's use of the term "swift boat." Instead Kerry calls for a general halt.
"I'd like to see us get to a better place in politics where the word Swiftboating is retired from the political vocabulary," said Kerry.
A recent poll indicates that Sestak, who once trailed Specter by a significant margin, is narrowing the gap in Pennsylvania's Democratic Senate nomination battle.
–CNN Senior Congressional Correspondent Dana Bash contributed to this report.