Mass. Senate race resumes after bombings shutdown

(CNN) - With one week to go until primary day, an election campaign suspended following last Monday's Boston Marathon bombings is trying to heat up.

The two Democrats and three Republicans running to fill the open U.S. Senate seat in Massachusetts immediately suspended their campaigns immediately after the terror attack, which left three people dead and more than 250 injured. But campaigning has resumed, and a feisty debate Monday night between the two Democratic candidates included fireworks over national security issues.

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Rep. Stephen Lynch attacked Rep. Edward Markey, the frontrunner in polling and fundraising in the battle for the Democratic nomination, for voting for a port security bill and against the creation of a joint terrorism task force.

"When the issue came up to create that joint task force, I voted yes, you voted no. I don't know how you spin that," said Lynch, according to local media reports.

Markey pushed back, saying if he did vote no, it was because the measures excluded "a provision that would have made the bill even stronger."

Markey and Lynch face off in a final debate Tuesday night in Springfield, Massachusetts, that was originally supposed to take place last week but was rescheduled following the marathon bombings.

The winner of the Democratic primary will face off in the June general election against the winner of next week's GOP primary between private equity investor and former Navy SEAL Gabriel Gomez, former US attorney Michael Sullivan, and state Rep. Daniel Winslow.

Gomez was running the marathon and finished just a few minutes before the bombs went off. He was not injured. Gomez appeared live on some of the cable news networks in the days after the terror attacks, giving a first-hand account of what he witnessed when the bombs went off and describing his search for his wife and children, who were at the finish line of the marathon at the time of the attacks.

Sullivan, who served as the acting director of the Bureau of Alcohol, Tobacco, Firearms and Explosives during President George W. Bush's second term, also appeared as a live guest on some of the cable news networks, including CNN, to analyze the law enforcement response.

Even before last week's bombings, the race had attracted limited attention, and lately was overshadowed by the news that longtime Boston Mayor Thomas Menino wouldn't run for re-election this November. Now the big question surrounding the Senate race is whether the bombings will influence the outcome of next week's primary elections.

"Whenever you have a pause in the race, it often benefits the front runner, because it leaves less time for the other candidates to make up ground," says Nathan Gonzales, deputy editor of the non-partisan Rothenberg Political Report.

The seat was left open when longtime Democratic Sen. John Kerry became secretary of state earlier this year. Democratic Gov. Deval Patrick appointed his former chief of staff, William "Mo" Cowan, to serve as interim senator until the special election in June.

- CNN's Ashley Killough contributed to this report.