The campaign of U.S. Rep. Joe Sestak, a retired admiral challenging Arlen Specter in the Democratic Senate primary, accused the incumbent Wednesday of "Swift Boat" tactics over an ad that implies the Navy fired him.

It was an escalation of the battle between the candidates one day after Sestak began statewide TV ads focusing on his biography and Specter responded by ripping the challenger's service record with another commercial.

"Joe Sestak, relieved of duty in the Navy for creating a poor command climate," a narrator says in the ad, referring to morale among Sestak's subordinates. The spot, which began running Tuesday, also smacks Sestak for missing 127 votes in the House last year.

Sestak's campaign sought to rally veterans to defend him by recalling how the Swift Boat Veterans for Truth tried to discredit Democrat John Kerry's service in a Navy patrol vessel in Vietnam during Kerry's 2004 presidential race against George W. Bush.

About two dozen veterans gathered Wednesday in an American Legion Hall in Clifton Heights to rebuke Specter and demand that he stop running the ad.

"We're all here because we're enraged at the fact that someone, anyone in the United States today, would question someone with 31 years of service," said Robert E. Kelly, a retired Air Force lieutenant general who flew 119 combat missions in Vietnam.

"We ought to get our act together in this country and recognize that the people who are serving today, who served yesterday, and will serve tomorrow deserve our respect," Kelly said.

The reference to the end of Sestak's military career comes from a Navy Times article that said he had been sacked in 2005 by the incoming chief of naval operations, Adm. Mike Mullen, now chairman of the Joint Chiefs of Staff, for treating staff poorly.

Specter's campaign says the ad is accurate and will not be pulled.

The Navy has never commented on the record about Sestak's reassignment, but it also has never disputed the accuracy of the story. Sestak, who was head of the Navy's warfare planning division, had a reputation for working subordinates hard that was intense even by military standards, Pentagon sources confirm.

But it is also true that Sestak, a protege of the preceding chief of naval operations, Adm. Vern Clark, had angered many in the top echelons of the service because he advocated cutbacks in the Navy's fleet.

"He challenged people who didn't want to be challenged," Clark told The Inquirer this month.

Sestak, who had been promoted to deputy chief of naval operations, a three-star position under Clark, has said Mullen wanted his own team. In 2005, Mullen reassigned him to a lesser job. Sestak retired in 2006 as a rear admiral and was elected to represent the Seventh District in the Philadelphia suburbs.

At the American Legion Hall Wednesday, the commander of the Veterans of Foreign Wars post in Folsom, where Sestak is a member, criticized Specter.

"The anger inside right now is unbelievable," said Jerry Gavin, 60, a former Army medic. If Specter "was here today, somebody would have to hold me back."

Still, the allegation that Sestak was bumped for being a nasty boss seems a far cry from the original Swift Boat attacks. The group accused Kerry of falsifying the record of a battle for which he was awarded the Silver Star, firing on unarmed civilians, and faking injuries to win a Purple Heart.

It's not the first time that Sestak's departure from the Navy has provided ad fodder for a political opponent: Republican Rep. Curt Weldon also brought it up during the 2006 race.

Veterans interviewed at the post yesterday acknowledged that Specter's ad presented a far less severe critique of Sestak's military service than the Swift Boat attacks that helped sink Kerry.

But criticizing a veteran's service at all is "disrespectful" and "unpatriotic," said Rocco Polidoro, a Springfield veteran. Some who served in Vietnam worry that attacks on a military member's service could erode improvements in the public image of the service since Vietnam, when civilians sometimes denigrated returning veterans.

And though Specter's ad isn't as vicious as the Swift Boats ads, it stings all the more because Specter is a veteran, they said.

"It's not as flagrant. It's more subtle," Tom Clay, 61, a Vietnam veteran and former Army helicopter door-gunner from Media, said about Specter's ad. "But it's there. A veteran should not attack another veteran's record."

Mike Hall, commander of the Clifton Heights post, agreed. "Vets don't go against other vets like that. It's a brotherhood."

Contact staff writer Thomas Fitzgerald at 215-854-2718 or tfitzgerald@phillynews.com.