Vice President Gore and his Democratic rival, former senator Bill Bradley, accused each other of lying and personal attacks in a sharply worded television debate tonight that reflected the tension of their close battle in next Tuesday's New Hampshire primary.

Bradley, who has been criticized by some supporters for passivity, sharply attacked Gore's credibility. "My question to you," he said at one point, "is why should we believe that you will tell the truth as president if you don't tell the truth as a candidate?"

Gore, appearing stung by the question, said with disbelief, "That's not a negative attack?" A moment later, the vice president told Bradley, "I haven't accused you of lying. We can have a disagreement . . . without you making negative personal attacks." And then, returning to his criticism of Bradley's signature health care proposal, he said, "If you feel like you're on the defensive on the substance of the issues, then change your plan. Don't shoot the messenger."

The accusations of lying and distortion marked a debate in which the rivals also challenged each other's positions on welfare reform, abortion rights and budget policy. Gore maintained his tone as a self-described "fighter," but instead of finding a punching bag at the other lectern, he encountered an opponent primed to dish out as much punishment as he received.

Going well beyond his previous rhetoric, Bradley said to Gore: "You know better. You know what you are saying is not true. And quite frankly, I wonder whether if you're running a campaign that is saying untrue things, whether you will be able to be a president that gets people's trust."

The 60-minute debate was the final scheduled confrontation between the two before New Hampshire holds its leadoff primary next Tuesday. Bradley badly needs a victory to offset the shellacking he received at Gore's hands in Monday's Iowa caucuses and to give him a plausible case to take to Democrats who will vote in California, New York, Ohio and other big states in the next round of primaries March 7.

Polls here show Gore and Bradley so closely bunched that the outcome is in doubt, with most suggesting that the past few days have strengthened the vice president's chances.

Gore focused his criticisms, as he has done for months, on elements of Bradley's health care plan that he said would eliminate Medicaid and substitute "a voucher or a subsidy" so small that no one in New Hampshire would be able to buy a private insurance policy as a replacement.

Bradley denied that, and then turned to the attack on his opponent's abortion record. Citing Hillary Rodham Clinton's criticism of New York Mayor Rudolph W. Giuliani as a latecomer to support of abortion rights, Bradley asked Gore if he thought consistency was important on that issue.

When Gore said yes, and declared that he had always supported a woman's right to choose, Bradley accused him of having a voting record in his early years in Congress that won an 84 percent approval rating from antiabortion groups. Gore repeatedly insisted he had always supported the Supreme Court decision establishing abortion rights, but conceded he had changed from being an early opponent of Medicaid-funded abortion to support of public financing of that procedure.

Then it was Gore's turn to go after Bradley for voting against the welfare reform bill of 1996 that the vice president said had moved 7 million people off the welfare rolls. Bradley replied that the same bill had taken away health insurance from a million youngsters and called it "a gamble with kids for the sake of reelection" of the Clinton-Gore ticket.

Yet another sharp exchange involved Gore's criticism of Bradley for supporting the spending cuts President Ronald Reagan proposed in 1981. Bradley tried to argue that if others had voted as he did, the huge budget deficits of the 1980s would not have occurred.

Gore shot back, "I just don't see how you can vote for Ronald Reagan's budget cuts and then try to campaign like Robert Kennedy."

Not to be outdone, Bradley said Gore's comment reminded him of what someone had said about Richard M. Nixon--that he could "chop down a tree and then stand on the stump and give a speech about conservation."

At another point, Bradley told Gore that voters want "a fresh start in Washington," suggesting that Gore could not supply it because "you are the favorite of the Washington lobbyists." It is impossible, Bradley said, to be "fighting for the people," as Gore regularly proclaims he is doing, "when you are working hand in glove with the special interests."

Gore would have none of it. In fact, he said, he had been fighting the lobbyists and special interests throughout his Washington career, including the oil companies on behalf of New England homeowners seeking lower fuel oil prices. "I fought you," he said to Bradley, "when you were pushing that amendment [on generic drugs] on behalf of the pharmaceutical companies" that have a large presence in New Jersey, which Bradley represented in the Senate.

Bradley insisted that his health care plan, with a provision favoring generic drugs, causes "heartburn" among the drug companies, and turned the charge back on Gore: "A thousand promises and a thousand attacks. That's been your campaign . . . a promise to every little special interest group. Attack, attack, attack every day. . . . Quite frankly, I think that people are fed up with it."

Gore said, "The people of New Hampshire know a negative ad when they see one. Ask them if they've seen a negative ad that my campaign has run. They did see that flyer that you apologized for." He was referring to a flyer distributed here by the Bradley campaign that accused Gore of distorting the Bradley health plan. Bradley said there were only a few hundred of them, and said comparing them to the Gore's television ads is like "comparing a gnat to an elephant. You're the elephant of negative advertising here."

The debate set a bitter tone that indicated there will be no restraint in either camp during the final five days of campaigning here. Bradley came into the press room after the debate and once again referred to Gore as having "lied in this campaign."

The stakes are high for both men. The Gore camp hopes New Hampshire will effectively end the Bradley insurgency, while Bradley counts on it restoring his credibility for the round of primaries on March 7, when he has ample financial resources to challenge the vice president.

Today began with Bradley backing away from a radio interviewer's invitation to discuss past controversies about Gore. "I think it's more important to give something for people to vote for than to vote against," Bradley responded when Dan Pierce of WGIR-AM in Manchester told him that he did not appear ready to "wade in there and start hacking."

Staff writer Ceci Connolly contributed to this report.