NEW YORK — Thomas A. Bolan, who played the silent partner to the flamboyant Roy M. Cohn in their politically potent law firm for three decades but was a power broker in his own right, died May 12 at his home in New York. He was 92.

The cause was heart failure, his son William said.

Mr. Bolan was a founder of the Conservative Party in New York, a patronage dispenser in the state for President Ronald Reagan, an adviser to Senator Alfonse M. D’Amato, and a confidant of William F. Buckley Jr.’s, serving as a board member of his National Review magazine.

Mr. Bolan and Cohn were an odd couple. Although Mr. Bolan was a name partner in their venerable Wall Street firm, which became Saxe, Bacon & Bolan, Cohn was more visible and histrionic. “A lot of people knew Roy,’’ said Michael B. Mukasey, a former federal judge and US attorney general and Mr. Bolan’s legal colleague. “A lot of people respected Tom.’’

Mr. Bolan was a Republican and Roman Catholic. Cohn was nominally a Democrat and gay. (Besides Cohn’s lover, Mr. Bolan was said to have been the only person who knew that Cohn had AIDS before he died in 1986.)

“To say the pairing of Tom with Roy Cohn was incongruous would be an understatement,’’ Mukasey said in an interview. “But Tom didn’t seem to notice.’’

Mr. Bolan was no introvert, though. He flew 35 bomber missions over Nazi-occupied Europe as a decorated navigator during World War II. He prosecuted accused Communists and racketeer Frank Costello and, in the 1950s, as an assistant US attorney in Manhattan, built a tax evasion case against the Rev. Adam Clayton Powell Jr., a Democrat who served as a US representative for Harlem.

As executive director of Feature Sports Incorporated, a firm formed by Cohn and William D. Fugazy, the limousine magnate, Mr. Bolan was also a fight promoter who handled the heavyweight championship bouts between Floyd Patterson and Ingemar Johansson.

And he was a die-hard New York Yankees fan. “I don’t make a trade unless I talk to him,’’ George Steinbrenner, then the team’s principal owner, once said.

But as a fierce advocate who sometimes became enmeshed in his clients’ business affairs, he, like Cohn, occasionally needed defending.

Thomas Anthony Bolan was born on May 30, 1924, in Lynn, Mass., to Thomas J. Bolan, a lawyer, and the former Margaret Cremin. He graduated from Bishop Loughlin Memorial High School in Brooklyn and earned bachelor’s and law degrees from St. John’s University.

He married the former Marie Gerst, whom he leaves, along with their sons, William and Douglas; their daughters, Mary Bolan and Jacqueline Engelhart; and eight grandchildren.

Mr. Bolan was a federal prosecutor when he quit in 1960 to join Cohn. The firm, which they bought four years later, eventually moved from the financial district into a town house on East 68th Street in Manhattan, where its partners included Stanley Friedman, the Bronx Democratic leader who was later convicted on federal corruption charges.

Mr. Bolan represented the Archdiocese of New York, headed the Catholic War Veterans organization, and helped establish the Human Life Foundation, which fights against abortion, euthanasia and genetic engineering.

After Reagan was elected in 1980, Mr. Bolan headed his transition team in New York and was named a director of the Overseas Private Investment Corp., the independent federal agency that helps US businesses invest in emerging markets. When D’Amato won election to the Senate that year, Mr. Bolan was the only aide who accompanied him on his first visit to Washington. He played a prime role in the senator’s recommendations for federal judges.

He represented a range of clients, including Donald Trump, but unlike Cohn, he shied away from mobsters and even spurned a lunch invitation from one who was Cohn’s client.

“These guys are always getting shot in restaurants,’’ he was quoted as saying in the 1988 book “Citizen Cohn’’ by Nicholas von Hoffman.

Mr. Bolan also represented Cohn, successfully defending him in 1971 against charges that he had defrauded a bus company, Fifth Avenue Coach Lines. Cohn thanked him for having “accomplished the impossible feat of making me sit there for three weeks without opening my mouth once, which is probably one of the main reasons I won.’’

Mr. Bolan was among those sued by the Securities and Exchange Commission as a director of the bus company, but he won.

Around 2000, though, he became entangled in what prosecutors said was a plot to bilk insurance companies of more than $200 million through a fake charity concocted by Martin R. Frankel, a stock trader.

In a scheme involving priests and a high Vatican judge, prosecutors said, Frankel had set up the charity, the St. Francis of Assisi Foundation, and then tried to use it to buy several US insurance companies. Mr. Bolan was a charity trustee.

In 2005, he pleaded guilty to failing to disclose that the foundation had made false representations to the Mississippi Insurance Department.

When the disciplinary committee of the Appellate Division of state Supreme Court in Manhattan ordered him to explain why he should not be censured, suspended, or disbarred, Mr. Bolan’s response, in character, contrasted strikingly with that of Cohn when Cohn was faced with the same situation.

Cohn fought to retain his license but was disbarred. He died six weeks later.

Mr. Bolan, who was 81, submitted an affidavit acknowledging “that he could not successfully defend himself against the charges.’’

He politely requested permission to resign.