Jesse Helms, the former North Carolina senator whose courtly manner and mossy drawl barely masked a hard-edged conservatism that opposed civil rights, gay rights, foreign aid and modern art, died early yesterday. He was 86.

Helms’ former chief of staff, James W.C. Broughton, said that the senator died at the Mayview Convalescent Center in Raleigh, N. C., where he had lived for the last several years. Helms had been in “a period of declining health” recently, Broughton said.

In a 52-year political career that ended with his retirement from the Senate in 2002, Helms became a beacon for the right wing of American politics, a lightning rod for the left, and, often, a mighty pain for presidents whatever their political leaning.

Ronald Reagan, a friend who could thank Helms for critical campaign help, once described him as a “thorn in my side.” Helms was known for taking on anyone, even leaders of his own party, who strayed from his idea of ideological purity.

“I didn’t come to Washington to be a yes man for any president, Democrat or Republican,” he said in an interview in 1989. “I didn’t come to Washington to get along and win any popularity contests.”

Perhaps his most visible accomplishments in the Senate came two decades apart. One was a 1996 measure that tightened trade sanctions against the Marxist government of Fidel Castro in Cuba. The other, a 1973 amendment to the Foreign Assistance Act, prevented American money from going to international family-planning organizations that, in his words, “provide or promote” abortion. He also introduced amendments to reduce or eliminate funds for foreign aid, welfare programs and the arts.

Lincoln D. Chafee, who entered the U.S. Senate in 1999 to complete the term of his father, John H. Chafee, who had died, yesterday said “Senator Helms was on the vanguard of the switching of the South from Conservative Democrats to Conservative Republicans.

“For the year that I was appointed to the Senate, I assumed my father’s seat next to Senator Helms in the Chamber. He used to tell me that during the interminable impeachment proceedings against President Clinton, he and my father would have an agreement to wake each other up if one of them fell asleep.

“I served on the Senate Foreign Relations Committee with him and we traveled to Mexico City together as he began to soften his stance with the international community. So often, as we advance in years, we mellow, and that was the case with Senator Helms in relation to our foreign policy.”

David A. Keene, chairman of the American Conservative Union, said recently that Helms’ contribution to the conservative movement was “incredibly important.”

In the Senate, Keene said, Helms was a rallying point for conservatives. As chairman of the Foreign Relations Committee, he supported Reagan on issues such as aid to the Nicaraguan Contras. “Without Jesse, it would have been hard for Reagan to hold the line,” he said.

Helms saw himself as a simple man — he even used the word “redneck” to describe himself — protecting simple American values from the onslaught of permissiveness, foreign influence and moral relativism. For 30 years he cut a familiar figure on the Senate floor, typically wearing horn-rimmed glasses, black wing tip shoes and, on the lapels of his gray suits, American flag and Free Masonry pins.

He was also well known for holding up votes on treaties and appointments to win a point. His willingness to block the business of the Senate or the will of presidents earned him the sobriquet “Senator No” — a label he relished.

In campaigns and in the Senate, Helms stood out in both his words and his tactics.

Trailing in a tough reelection fight in 1990 against a black opponent, Harvey Gantt, the former mayor of Charlotte, Helms unveiled a nakedly racial campaign ad in which a pair of hands belonging to a white job-seeker crumpled a rejection slip as an announcer explained that the job had been given to an unqualified member of a minority. Helms went on to victory.

His bruising style and right-wing politics won him many friends in his home state and across the nation, but he also created a legion of enemies. Millions of dollars were raised outside North Carolina both from those who flocked to his ideological banner and from those who ached to see him defeated. He never won more than 55 percent of the vote in five campaigns for the Senate.

“He was a very polarizing politician,” said Ferrell Guillory, a veteran North Carolina journalist. “He was not a consensus builder. He didn’t want everybody to vote for him. He just wanted enough.”

In 1970 Helms switched his party registration from Democrat to Republican. Two years later, he upset the favorite by a convincing 120,000 votes to win a Senate seat.

The first few years as a senator were difficult for Helms. He was overshadowed by the state’s better-known senator, Sam Ervin. His conservative idol, President Richard M. Nixon, was driven from office by the Watergate scandal, and his vote against Nelson Rockefeller, President Ford’s choice for vice president, alienated him from the party’s leadership. He was in debt. He considered retiring after his first term, but changed his mind.

“I looked around the Senate and thought that it needed conservative votes and that it didn’t have too many,” he said.

With Journal reports by Katherine Gregg