The way Sen. Conrad Burns' re-election campaign is going, the folksy 71-year-old Republican might rather take a turn on a bronco than try to explain his links with disgraced lobbyist Jack Abramoff back in Washington.

The "Eastern liberal press" is to blame for his troubles, says Burns. Some of his former aides worked for Abramoff and two current aides took a trip to the 2001 Super Bowl in the lobbyist's jet. The senator received about $150,000 in donations from Abramoff, his clients and his associates, which he has since returned or given to charity.

Montana voters, Burns says, "will make the right judgment call."

Judging from the springtime polls, the call will be a close one, and not necessarily in his favor.

Burns faces three primary opponents on Tuesday, evidence enough of the widely held view even among Republicans that the three-term lawmaker is vulnerable. His renomination seems secure, but a weak showing would further embolden Democrats who have made him a top target for the fall.

In an appeal to conservatives, Burns launched a radio ad Wednesday that focuses on his vote against a bipartisan Senate bill with increased border security that also contains a guest worker program and a chance at citizenship for many illegal immigrants.

"Amnesty could give illegal aliens Social Security, and even in-state tuition, with your taxes," argues the ad, which notes that Burns voted against "amnesty because it rewards those who have broken the law."

Democrats pick an opponent on Tuesday, either state Senate president Jon Tester or state auditor John Morrison, and recent polls show the general election campaign highly competitive.

Around the stands at the Bucking Horse Sale, an annual fiesta centering on the sale of rodeo broncs and bulls that also attracts ambitious politicians, talk turns to Abramoff. The Republican lobbyist pleaded guilty to federal corruption charges earlier this year and agreed to cooperate in a congressional influence-peddling investigation.

"I liked Conrad from the very first time I saw him," said Charlie Gephart, 70, a sheep rancher. "He's in a little trouble right now with the money he's taken from Jack Abramoff, but he's done a lot for the state of Montana and I am going to continue to vote for him."

Burns' campaign seeks to tap into that with commercials that stress his accomplishments such as bringing millions of dollars to the state as a member of the Senate Appropriations Committee.

He also addressed the Abramoff issue head-on, calling the lobbyist "the guy who ripped off his Indian clients for millions and lied to anybody and everybody."

"I don't know who Abramoff influenced, but he never influenced me," Burns said in the spot.

Tester has called for Burns to resign, and Morrison has argued that the Republican is "in deep trouble with the law."

"Montanans know that and that's why they are saying all over this state that they think it's time for a change," Morrison said. "And it's not just Democrats who are saying that, it's Republicans and independents, too."

The Bucking Horse Sale roughly doubles the population around Miles City (about 8,000), turning it into a major event in a significant chunk of eastern Montana. Legend has it that a young Edward M. Kennedy briefly rode a bucking horse when he was campaigning for his brother, John, during the 1960 presidential race.

Burns greets well-wishers and old friends at a familiar stomping ground; his first Bucking Horse Sale was in the early 1960s when he was working for an agricultural group. He admits that even supporters might question his ties to Abramoff but argues that it won't matter to voters.

"In this country, your word is your bond. There's been some phonies come through here but they didn't last very long," Burns said. "Just let people look at your record, never lose faith in the people. They'll make the right judgment call."

A Mason-Dixon poll conducted in late May for the Lee Newspapers of Montana showed Burns with a 38 percent approval rating, down from 51 percent six months ago.

Tester and Morrison are locked in a tight race for the Democratic nomination. Morrison has held the advantage in fundraising, but Tester has gained some traction with campaign ads showing him working on his family's organic farm in Big Sandy, Mont.

Morrison also has faced questions about his handling of a securities investigation while he was state auditor because it targeted the fiance of a woman he had an affair with. He said he took no role in the case.

"I think, given the overall importance of ethics, if we're just looking at one issue, that Tester is better placed than Morrison," said Craig Wilson, a Montana State University-Billings political scientist who has observed Montana politics for 40 years.