Updated

SALT LAKE CITY -- U.S. Sen. Bob Bennett said Friday his seniority allows him to bring more change in Washington than any of his seven GOP opponents, using the final debate before Utah Republicans narrow the field to try to stave off criticism he's no longer conservative enough to represent them.

Bennett's bid for a fourth term is at stake as about 3,500 Republican delegates gather Saturday to choose the party's nominee -- or two candidates to face off in a June primary. Bennett is in serious danger of being defeated at the convention, with recent delegate surveys showing him in third place behind attorney Mike Lee and businessman Tim Bridgewater.

Bennett will need at least 40 percent of delegate votes to force one of his opponents into a primary. Any candidate who gets 60 percent of delegate votes at the convention wins the nomination outright, avoiding a primary altogether.

Bennett debated Lee, Bridgewater and conservative activist Cherilyn Eagar Friday on KNRS radio.

Bennett said charges by his opponents that he is not a conservative are false, noting he's been endorsed by the National Rifle Association and has high ratings from other conservative groups.

"I don't have any understanding how somebody can look at my record and say, 'Gee, this guy is a liberal.' That is nonsense," he said. "The reality is I'm considered in Washington as one of the most conservative members of Congress."

But he has come under attack for voting for a massive financial bailout, co-sponsoring a bipartisan bill mandating health insurance coverage and for aggressively seeking earmarks for Utah.

Bennett contends his opponents are filled with slogans, but have no practical solutions.

"I would have more influence in turning the ship of state than any of them would," Bennett said. "This is not a speed boat that you turn in a minute. This is an ocean liner that's going strongly in one direction and it needs the kind of thoughtful approach to getting it done that I believe I can bring to it."

Lee disputes that notion. He said he believes in a balanced budget amendment and using the Constitution as a guide to determine what federal programs should be in place.

"We all need to remember the constitution provides real, practical solutions. It's not just sound bites, it's not just talking points, it is a document that sets in motion ancient principles, wise principles, inspired principles, that can protect us from an overreaching government," he said.

Bennett said there would be little difference between how he and his opponents would vote.

But Bridgewater seized on one difference Friday, saying he's opposed to the importation of foreign nuclear waste.

Salt Lake City-based EnergySolutions Inc. wants to import up to 20,000 tons of low-level radioactive waste from Italy. After processing in Tennessee, about 1,600 tons would be disposed of in Utah.

In response to the company's application, the House passed a bill banning the importation of nuclear waste. It's languishing in the Senate largely because of Bennett's objections.

Bennett, who has received $9,000 from the company's political action committee and thousands more from company employees in the past year, contends a nationwide ban is premature and may harm other states who want the material in the future.

Lee, who is fighting Utah in court to ensure EnergySolutions can dispose of the Italian waste in Utah, says a ban shouldn't be in put in place until EnergySolutions can build disposal sites abroad.

The Utah site is the only place 36 states can dispose of low-level radioactive waste, and supporters of the waste ban contend it should be reserved for domestic waste.

"Those countries have to deal with their own waste. They have to come up with their own solutions. Utah, I believe, should not become that dumping ground," Bridgewater said