The war of words between Rep. Joe Sestak (D-Pa.) and Sen. Arlen Specter
(D-Pa.) in Pennsylvania’s Senate primary has Democrats worried.

In the latest salvo, Sestak accused Specter of swift-boating his military record.

{mosads}The senator released a 30-second spot earlier this week that said the former Navy admiral was relieved of duty at one point for creating a “poor command climate.”

Sestak invoked Vice President Joe Biden in his response, pointing to a statement Biden said in 2008 regarding the swift-boat tactics used in the presidential election.

“Swift-boating is not going to work this time, and the reason it’s not is, number one, I’m going to smack ‘em right square in the chops,” Biden said at the time.

The Specter campaign has also been aggressive, calling Sestak’s first TV ad — which depicts him in his Navy uniform — a “violation” of Defense Department policy.

“Sestak’s TV spot uses multiple photos and videos of his time in the Navy but lacks the [Department of Defense] disclaimer required for use in a political commercial,” the Specter camp said in a statement. It called on Sestak “to explain his TV ad’s apparent violation of various Department of Defense regulations regarding the use of military images.”

“He can’t campaign on his Navy credentials but at the same time say the numerous public criticisms of his career and firing are off-limits,” Christopher Nicholas, Specter’s campaign manager, told The Hill.

Meanwhile, senior Democrats are preparing to circle the wagons around Specter in order to limit the damage ahead of what’s expected to be a tough general-election campaign against former Rep. Pat Toomey (R-Pa.).

“You’re going to see some of the party leadership from every corner of the state led by Gov. Ed Rendell and hopefully by our friends in the White House talking about why it’s important” to reelect Specter, Pennsylvania Democratic Party Chairman T.J. Rooney told The Hill. “We’re going to be on the phones and we’re going to be in every hamlet in Pennsylvania talking about why it’s important to make sure Arlen Specter prevails.”

Biden is scheduled to appear at a whistle-stop rally with Specter in the Scranton area Friday. And if the polls tighten ahead of the May 18 vote, an adviser to Rendell said the two-term governor would rally his base of support in the Philadelphia area for Specter.

A recent Quinnipiac University poll showed Specter with a 53-32 lead over Sestak among likely Democratic primary voters. Sestak is trying to make that ground up by attacking Specter for having been a Republican and a supporter of President George W. Bush. A recent Sestak campaign mailer hit Specter on voting for Supreme Court Justices John Roberts and Samuel Alito, a source said.

Observers expect there to be more “venom” in the attacks as the May 18 primary vote approaches.

“The venom is going to come from Sestak, it’s not going to come from Specter,” said Rooney, noting the state party’s executive committee has endorsed Specter. “People know Arlen Specter. No one knows Joe Sestak. In order to get to Arlen Specter you’ve got to de-bark him, and that’s clearly the road map or the plan they intend to employ.”

The Sestak camp maintained it plans to run a positive campaign.

“While Joe Sestak is running a positive TV ad about his accomplishments for people and his agenda for changing Washington, Specter has launched a Republican-style negative campaign in his TV ads,” said Jonathon Dworkin, a spokesman for Sestak’s campaign. “It will speak volumes to Democrats that Joe Sestak is running on his record for working families, while Arlen Specter runs away from his.”

Rooney and others are worried that a nasty primary could hurt Specter in the general election.

“Sometimes primaries are a good thing and sometimes not. In this case, certainly not,” Rooney said. “It costs a lot of money to go through these exercises.”

He said the GOP will be able “stockpile” $8 million “while we’re going after each other.”

“I wish we didn’t have this one, but you can’t put the genie back in the bottle.”

But other Pennsylvania operatives noted that Sestak’s main line of attack — that Specter was a Republican — may actually help the senator in the general election because he’ll appear as a centrist.

“Going after him for a being a Republican is certainly not going to hurt [Specter] with voters who aren’t very political,” said Terry Madonna, who directs the center for politics at Franklin and Marshall College in Lancaster, Pa.

Still, Toomey’s campaign sounds convinced that the primary will do some damage to the incumbent.

“If there had been any doubt before, this Democratic primary has categorically proven that Arlen Specter will take any position on any issue in order to preserve his political career,” said Nachama Soloveichik, a spokeswoman for Toomey’s campaign. “That’s not going to sell in a general election, and that’s why large majorities of Pennsylvanians are consistently saying that Arlen Specter’s 30 years in Washington are enough.”

— This article was updated at 9:29 p.m.