Mr. Burns speaks with constituents in his Senate office in 2006. (Melina Mara/The Washington Post)

Conrad Burns, a onetime cattle auctioneer who parlayed his down-home appeal into three terms as a Republican senator from Montana, reaping federal dollars for his state as well as criticism for his impolitic, at times offensive, off-the-cuff remarks, died April 28 at his home in Billings, Mont. He was 81.

The cause was complications from a stroke in 2009, said a daughter, Keely Godwin.

Mr. Burns served from 1989 to 2007 in the Senate, where he made “weighty speeches on foreign policy and the future of the Internet,” it was observed in the Almanac of American Politics, even while cutting “the figure of a stereotypical Westerner, picking his teeth with a pocketknife, chewing tobacco, telling deadpan jokes.”

He lost his seat in 2006 to a Democratic challenger, then-state Senate President Jon Tester, after revelations that Mr. Burns had received $150,000 in campaign contributions — among the highest amounts of any member of Congress — from disgraced lobbyist Jack Abramoff and his associates.

The son of Missouri ranchers, Mr. Burns had established himself in Billings, Mont., as a livestock auctioneer, then built a network of 29 radio and six television stations devoted to agricultural news. He was elected Yellowstone County commissioner in 1986 and two years later defeated an incumbent Democrat, John Melcher, for a seat in the Senate. Mr. Burns came to Washington promising never to “take a chew under the Capitol dome.”

He did not come to the Senate “deeply steeped in politics and governance,” Norman J. Ornstein, a congressional scholar at the American Enterprise Institute, said in an interview, adding that Mr. Burns had some “rough edges.” But “I liked him because he was very unpretentious,” Ornstein said. “He knew who he was.”

Mr. Burns obtained a seat on the Commerce Committee, chairing the subcommittee on communications, and on the powerful Appropriations Committee, where he led the Interior subcommittee.

On the former, he supported deregulation and the cultivation of online commerce. On the latter, he helped direct federal funds to Montana. Especially as his seniority increased, he became known as an effective advocate for his constituents.

When drought hit farmers, Mr. Burns lobbied for federal relief similar to the funds given to victims of floods and hurricanes. A family statement on his death emphasized his attention to Montana interests including farming and ranching, as well as rural telecommunications and health care.

But Mr. Burns also drew the ire of many in his state and elsewhere over his stream of gaffes insulting groups including but not limited to African Americans, Arabs and immigrants.

“I can self-destruct in one sentence,” Mr. Burns once said. “Sometimes in one word.”

In 1991, after the passage of a civil rights bill, Mr. Burns invited a mixed-race group of lobbyists to an auction. When the prospective guests inquired what goods were to be sold, he responded, “Slaves.”

Mr. Burns later clarified that his phrasing referred to volunteers who agreed to do chores or other jobs for a charitable cause.

During his reelection campaign in 1994, he relayed to the Bozeman Daily Chronicle a meeting with a Montana rancher who asked him how he managed to live in Washington with “all those [n-----s],” using a racial slur for African Americans. By his account, Mr. Burns replied that it was a “hell of a challenge.”

The senator later apologized, saying that the episode represented “views which I do not condone and do not share.” He also remarked that “it’s always a challenge when you bring different cultures and beliefs together.”

On another occasion, he referred to Arabs as “ragheads.”

During his final reelection campaign, Mr. Burns was widely rebuked for telling firefighters that they were doing a “piss-poor job” combating a wildfire in Montana. By that time, Mr. Burns faced withering scrutiny over his ties to Abramoff, who pleaded guilty in January 2006 to fraud, tax evasion and conspiracy to bribe public officials.

As chairman of the Interior subcommittee, Mr. Burns oversaw legislation involving Indian affairs. Abramoff, who admitted to defrauding Indian tribes he represented, told Vanity Fair magazine that his clients received “every appropriation we wanted” from Mr. Burns’s subcommittee.

Mr. Burns said that he did not personally know Abramoff and that he had not realized the lobbyist’s relationship with tribes that donated to his campaign.

“I don’t know who Abramoff influenced,” Mr. Burns said in a campaign advertisement, “but he never influenced me.”

Mr. Burns had announced in 2005 that he would return the Abramoff funds, but the scandal took its toll. He lost to Tester by fewer than 3,600 votes.

In 2008, the Justice Department closed an investigation of Mr. Burns’s involvement in the Abramoff matter, without bringing criminal charges.

Conrad Rae Burns was born in Gallatin, Mo., on Jan. 25, 1935. After studying agriculture at the University of Missouri, he served in the Marine Corps for two years. He moved to Montana as a representative for a trade publication devoted to polled Hereford cattle. He sold his agricultural broadcast network as he launched a career in politics.

Mr. Burns easily won reelection in 1994 but faced greater difficulty in 2000 when he ran for a third term, despite a promise to stay in Washington for only two. He defeated Democrat Brian Schweitzer, later elected Montana governor, 51 percent to 47 percent.

After his loss in 2006, Mr. Burns worked for a Washington lobbying firm, Gage Business Consulting. He frequently offered his services as an auctioneer at charitable functions.

His daughter Kate Burns died in 1985. Survivors include his wife of 48 years, the former Phyllis Kuhlmann, of Billings; two children, Keely Godwin of Durham, N.C., and Garrett Burns of Alexandria, Va.; a sister; and three grandchildren.