Sterling Tucker, a Washington-based civil rights organizer and politician who in 1974 became chairman of the first popularly elected D.C. Council in more than a century, died July 14 at his home in the District. He was 95.

The cause was congestive heart failure and kidney failure, said a grandson, Jason Jeffery.

Mr. Tucker was a central player in District politics and political activism for more than three decades. He rose to prominence in the 1960s as director of the Washington Urban League, a civil rights organization, and as a principal organizer of the 1968 demonstration known as the Poor People’s Campaign.

The following year, he was appointed by President Richard M. Nixon as D.C. Council vice chairman. At the time, the District was governed by presidential appointees subject to the oversight of Congress, and the chairman of the House District Committee and other members of Congress exercised sweeping authority over city affairs.

As vice chairman, Mr. Tucker worked with other political leaders and activists to bring about long-sought home rule for the District. He resigned as the Urban League’s director in 1974 and ran that year virtually unopposed for D.C. Council chairman in the first election after home rule was enacted.

Four years later, Mr. Tucker used the perch to run for mayor. He finished a close second to Marion Barry, the charismatic former civil rights activist then serving on the council. That election sent Barry into his first of four terms as the city’s chief executive.

As council chairman, Mr. Tucker was perceived as a steady leader who focused on matters such as rent subsidies for the working poor, the elderly and those with disabilities. In a 1978 editorial, The Washington Post described Mr. Tucker as “a thoughtful technician” who was “familiar with the nuts and bolts of the machinery of city government.”

In April 1978, Mr. Tucker announced that he was running for mayor. In a three-way Democratic primary that included Barry and the incumbent, Walter E. Washington, Mr. Tucker was seen by many as the odds-on favorite and the “safe” candidate.

He asserted that Mayor Washington had “lost control of the administration” of the city government. Washington by then had been mayor for 11 years — first by appointment and later as the city’s first elected leader — and was handicapped by a municipal bureaucracy that was widely perceived as cumbersome and unresponsive.

Barry had built his reputation in the 1960s and early 1970s and was seen as a noisy and militant street protester. He promised change at the top, but there was uneasiness over the extent and degree of change that might come with a Barry administration.

Mr. Tucker cultivated an image as the middle-ground candidate. He promised greater efficiency in city government, better delivery of city services, comprehensive city planning, improved schools, better housing and a clean environment.

But he lacked Barry’s easy rapport with voters in down-and-out city neighborhoods. Barry also had the editorial endorsement of The Post, which wrote that “with Mr. Barry, we see the prospect that things will be different and better.”

On Election Day, Barry prevailed by 1,500 votes. Mr. Tucker never won another city election despite several attempts. In hindsight, civil rights historians have said that Barry’s confrontational and aggressive style in demanding rights and equality was more suited to the times than the moderate approach associated with Mr. Tucker’s Urban League and the “black establishment” represented by Walter Washington.

“History passed Sterling and Walter Washington by,” said Bernard Demczuk, a historian of African Americans in Washington.

Mr. Tucker had been deeply affected by his experience with the Washington Urban League, where he worked for 13 years before his D.C. Council appointment. The organization focused mainly on jobs and employment opportunities for African Americans. Mr. Tucker was one of the chief architects of the league’s decision to organize poor blacks in city ghettos and became recognized as a key spokesman for the District’s disenfranchised African American community.

He tended to work within the system — street protests and militant confrontation were not his style.

But in June 1968, Mr. Tucker helped coordinate the “National Day of Support” demonstration on the Mall. It was seen as the culminating event of the Poor People’s Campaign against poverty and joblessness organized by the Southern Christian Leadership Conference.

The event came only weeks after the assassination of the Rev. Martin Luther King Jr. and the rioting that followed. Washington was a city on edge.

“We hope to create not a climate of fear, but a climate of hopefulness,” Mr. Tucker said at the time. “Poverty and violence are about to bring our nation down if we do not stand up now.”

Sterling Tucker was born Dec. 21, 1923, in Akron, Ohio, the fourth of eight children. His father was a workforce foreman for the municipal government. “I guess I was poor,” Mr. Tucker told The Post in 1978, “but I didn’t know it. We had clean clothes, with patches mended on. I felt very comfortable.”

Mr. Tucker was a 1946 graduate of the University of Akron, where he also earned a master’s degree in psychology in 1950. At college, he met his future wife, Alloyce Robinson. She died in 2004 after 56 years of marriage.

Survivors include two daughters, Michele Jeffery of Washington and Lauren Tucker Cross of New Hempstead, N.Y.; and four grandchildren.

While in college, Mr. Tucker bused tables at a fashionable Akron restaurant, the Garden Grille. He noticed that African Americans, despite Ohio’s public accommodations law, were routinely turned away.

On a Sunday off, Mr. Tucker and Robinson and another African American couple showed up at the restaurant as customers. They insisted on being served in the dining room — not at the counter or somewhere out of sight, where the owner wanted them to sit. They were served their meals in the dining room, but two weeks later, Mr. Tucker was fired from his 50-cents-an-hour job there.

He worked for the Urban League in Canton, Ohio, and in New York before joining the Washington office in 1956.

While in Canton, according to an indictment handed up by a federal grand jury in Cleveland, Mr. Tucker filed fraudulent income tax returns by over-claiming allowable deductions. He pleaded no contest to the charges and in 1959 was fined $500 and placed on probation. President Lyndon B. Johnson pardoned him in 1966.

During his career in Washington politics, Mr. Tucker was shadowed by accusations of financial impropriety, but none led to a conviction.

In 1979, after losing to Barry in the Democratic mayoral primary, Mr. Tucker was appointed to the U.S. Department of Housing and Urban Development as assistant secretary in charge of fair housing and equal opportunity programs. He served until the end of the Carter presidency and later opened a consulting firm, Sterling Tucker and Associates.

He considered running for mayor again in 1982 but found scant enthusiasm among his former supporters. He decided instead to run for his old seat as D.C. Council chairman. After Mr. Tucker lost that race, Barry nominated him to lead the city’s Board of Elections and Ethics in 1983, but the council rejected the nomination.

In 1989, Barry named him the city’s top anti-drug adviser. Six months later, Barry was arrested on charges of cocaine possession in an FBI sting operation at a downtown hotel. He would later be convicted and serve prison time.

In 1990, Mr. Tucker resigned as the District’s anti-drug chief to run for D.C. delegate to the House of Representatives. Mr. Tucker won an endorsement from a coalition of 88 Washington ministers and argued that his experience in government made him the most qualified candidate for the job. But Eleanor Holmes Norton, a civil rights activist and law professor at Georgetown University, won the contest.

Mr. Tucker did not seek public office after that. He ran his consulting business, served on several boards and was president of the board of trustees of the National Theatre.

As a civil rights leader, he never wavered from what was perceived in the 1960s as the “moderate” position.

“Black rage is not diffuse. We know its causes and its targets,” he wrote in the 1971 book “For Blacks Only.” But “passion alone is poor strategy. . . . When I say I cannot afford to be angry, I mean that like a fighter, like a football player I cannot afford to lose my head. The rage must be controlled, channeled, used rationally. I cannot indulge in emotional catharsis. I cannot afford that luxury.”