But Lautenberg, in a radio debate aired New Jersey 101.5 FM, argued that Andrews has not been an effective advocate for ending the war.
"I never heard Rob Andrews make a statement that would seriously get us out of there," he said.
Andrews accused Lautenberg of misstating his own record on the war.
"The senator has just completely misrepresented his position," Andrews said, pointing out that when he was running for the Senate in 2002, Lautenberg said he supported invading Iraq.
The third candidate, Morristown Mayor Donald Cresitello, said he had opposed the war from the start. All three said they wanted a timetable to remove troops.
It was the first debate for the three Democratic candidates for U.S. Senate.
Debates themselves had been a point of contention in the campaign. When Andrews surprised the New Jersey political world by entering the race this spring, he challenged Lautenberg to a series of debates, then held several news conferences to criticize him for not responding.
Lautenberg eventually agreed to Thursday's debate and another scheduled for Friday on New Jersey Network public television.
On Thursday, the candidates took questions from callers, each other and moderator Eric Scott.
On some policy areas, they had similar views: All three support a higher minimum wage and repealing tax breaks for the wealthiest Americans.
For the most part, though, Andrews and Lautenberg sparred while ignoring Cresitello, who tried to interrupt and steer the debate toward what he saw as failures by the other two in their time in Congress.
Lautenberg was in the Senate from 1983 to 2001, then returned in 2003. Andrews has been in the House since 1990.
As it has been throughout the race, Lautenberg's age, 84, was discussed.
But Andrews, 50, who has aired a commercial that notes Lautenberg will turn 91 during his term if he's elected, said it's not exactly Lautenberg's age that's a problem.
"I think that he's not effective in the U.S. Senate. I don't think age has anything to do with it," Andrews said. "I think it's his level of commitment for the next six years."
Lautenberg said Andrews has brought up age repeatedly.
"Congressman Andrews has done everything he can to assault my age. He doesn't talk about my effectiveness," he said. "He doesn't know effectiveness when he sees it. He hasn't had any of it in the U.S. Congress."
Andrews agreed that he would bring up Lautenberg's age only when asked about it.
Lautenberg quipped that he wouldn't either: "I will not bring up age again, I promise you that."
But on the final question, when the candidates were asked to say something nice about each of their opponents, Andrews apparently couldn't resist. "Sen. Lautenberg, thank you for serving our country in the Second World War," he said.
