Lautenberg, seeking a fifth term, withstood a challenge from U.S. Rep. Rob Andrews, who reminded voters Lautenberg would be nearly 91 by the end of a fifth term. Lautenberg, 84, is the third-oldest senator.
Zimmer, a former congressman, said he's already accepted a June 13 debate that would be hosted by the New Jersey Association of Counties.
"The voters deserve to hear our views and see what each of us has to offer, consider our ideas and determine who is best-suited to find the solutions for a better New Jersey," Zimmer said at a Statehouse news conference.
Lautenberg's campaign didn't immediately respond, but Lautenberg on Tuesday night made no debate commitments.
"He'll have plenty of time to talk and make requests," he said of Zimmer.
Lautenberg debated Andrews twice and Andrews tried to make Lautenberg's refusal to debate more an issue. Zimmer said his challenge was different than Andrews' because he and Lautenberg have "major philosophical differences."
"It will be a spirited debate between Sen. Lautenberg and myself, the un-Lautenberg," Zimmer said.
Zimmer highlighted his philosophy of less government spending.
"Frank believes it is OK to vote for $250 million bridge-to-nowhere in Alaska in exchange for a few hundred grand for blueberry research here at home," Zimmer said.
Zimmer, 63, served in the House from 1991 to 1997, but lost the 1996 U.S. Senate race and a 2000 House race. He has been a Washington lawyer and lobbyist.
He said he wouldn't focus on Lautenberg's age.
"The issue in this campaign is about effectiveness," Zimmer said, saying Lautenberg has passed one bill - a measure to rename the West Milford post office - in his last six years in the U.S. Senate.
Lautenberg on Tuesday night quickly sought to link Zimmer and Republican presidential candidate John McCain to President Bush, whom he blamed for the Iraq war and economic woes ranging from the mortgage crisis to soaring gas prices.
"That's why I'm running for re-election for the Senate, to bring change back from those failed policies," Lautenberg said. "We're going to put our country back together, right back on the right path."
With 99 percent of precincts reporting, nearly 11 percent of New Jersey's 4.95 million registered voters cast ballots. That's similar to the turnout in recent June primaries in the state.
