On topics that ranged from the war in Iraq to Social Security, the incumbent Republican and Durston, an emergency room physician, jousted and sparred, often in unusually harsh terms.

Opposition to the war in Iraq is what drew Durston into the 3rd Congressional District race in February, and he barely restrained his disdain for Lungren, who backs the Bush administration policies there.

The Vietnam veteran noted that Lungren had never served in the military, saying "I don't have respect for anyone" who favors the war but has never served or fought in one.

Moments later, it was Lungren's turn for the sharp rebuke.

"Dr. Durston happens to have more respect for the United Nations than the United States government," Lungren charged, raising boos from the audience.

Durston is fighting a tough campaign against Lungren, who has raised much more money in the 3rd District that is considered safely Republican. Today, Durston will pick up the endorsement of former Sen. Max Cleland, a Georgia Democrat who went on to head the Veterans Administration under President Clinton.

Thursday's debate was sponsored by the League of Women Voters and the South County Citizens for Responsible Growth. Held in a packed room at the Robert L. Trigg Education Center, it was the first of three scheduled between them before the Nov. 7 election.

The crowd seemed to be dominated by Durston loyalists. Because the questions were taken in writing from the crowd, many were worded in a fashion favorable to him.

While the topics were diverse, the most heated exchanges occurred over defense issues and foreign policy. Lungren was visibly angered at one point when the crowd openly laughed at him during an exchange over whether torture should be permitted under any circumstances.

"Some people confuse torture with aggressive means of interrogation," Lungren said.

When the chiding subsided, Lungren said he does not consider sleep deprivation to be torture and said tough interrogation tactics had saved lives because of the information learned.

"We should establish what the boundaries are," Lungren said. "If there are circumstances to allow more difficult treatment, we ought to state it in law."

But Durston, a former head of Physicians for Social Responsibility in the Sacramento area, said there is no situation where mistreatment of prisoners is appropriate.

"It's most telling what he didn't tell you," Durston said of Lungren. "He didn't agree with me with unequivocal opposition to torture."

The differences widened when the topic later turned to immigration.

Lungren said he backed the construction of a border fence to make illegal entry into the country more difficult. Durston compared such a fence, recently approved by Congress, to the Berlin Wall.

"I'd say building walls is a medieval concept," he said. "We need to advance beyond medieval thinking."

Durston then challenged Lungren over his use of the term "illegal aliens" to describe those in the country without documentation.

"I address them as human beings," he said.

With clear signs of frustration showing, Lungren said "I refer to them as illegal aliens because those are the words used in the law."

During an exchange on the Patriot Act, the crowd again heckled Lungren, drawing a sharply worded retort from him.

"It is really interesting when people think they have more to fear from their own government than al-Qaida," he said. "I am sorry you feel that way."

When the topic changed to the Medicare drug prescription plan for senior citizens, Lungren said he thought it was working pretty well but at higher cost to the government than he would like.

Durston condemned it completely, saying "it is not a benefit so much for seniors but a benefit for the drug companies."

In closing summations, Lungren emphasized his bipartisan successes in Congress, including recent passage of a port security bill he co-authored with California Rep. Jane Harman, the senior Democrat on the House Intelligence Committee.

Durston emphasized the wide chasm between him and Lungren, implying that re-electing Lungren to a second House term would itself be a national security mistake.

"If we lose ... the future of our government is imperiled," Durston said to wild applause.