(Dave Roback/AP)

For a second straight night, the two Democrats running for a Massachusetts Senate seat slammed one another for votes on homeland defense, with Rep. Edward J. Markey charging that Rep. Stephen F. Lynch had taken a page "right out of the Karl Rove swiftboat playbook" with the claims he was making.

Lynch opened the debate by hitting Markey for voting against five Homeland Security Department appropriations bills, a joint terrorism task force measure, and a port security bill.

Markey countered with a references to both GOP strategist Karl Rove and a 2004 effort to discredit then-presidential candidate John Kerry's military record. "He's taken a page right out of the Karl Rove swiftboat playbook," Markey said. "And it's very sad, especially just one week after what just happened in Boston and Cambridge and Watertown."

"I didn't take the page from Karl Rove's playbook," retorted Lynch. "I took the page from your voting record."

The questions about homeland security were raised eight days after the Boston Marathon bombing that killed three people and injured more than 200 others. Markey and Lynch also sparred over security issues in Monday's debate.

Markey was feistier Tuesday night, offering stern rebukes against Lynch where he was more reserved a night earlier. Lynch, too, was heated, calling Markey a "liar" at one point, a charge that prompted Markey to say his opponent was being "inappropriately personally insulting."

Markey said he voted no "every time there was a homeland security bill that did not ensure that we screened for bombs on passenger planes. I voted no every time there was a bill that did not screen for nuclear weapons that could come into the Port of Boston." He pointed out that every other member of the Bay State's congressional delegation opposed the joint task force except Lynch.

Tuesday's debate was the final one ahead of the April 30 special primary election for the seat once held by Kerry. Polls show Markey is the front-runner. Lynch and Markey both put their campaigns on hold for about a week following the Boston bombings, returning to race in which Markey was still the candidate to beat.

Lynch said he disagrees with the Massachusetts law that legalized medical marijuana, while Markey said he was for it. The two also sparred over the federal health care reform act. Markey slammed Lynch for voting against the bill.

"When Steve was needed most, he did not stand up for the health-care needs of people in this state," Markey declared.

Lynch defended his vote, saying the measure ceded far too much to insurance and pharmaceutical companies. "We not only paid the ransom, we gave them the hostages, too," he said.

Throughout the debate, Lynch sought to pitch himself as more of a people person than Markey. "Ed is is great on policy, I give him that. But I also think I am great on people," Lynch said.

Markey rejected Lynch's classification. In his closing statement, he asked Lynch, "who were you standing up for when you cut all that homeland security money?"