On the night Harry L. Thomas Jr. would admit publicly that he had stolen city money and was resigning from the D.C. Council seat his family had held for much of the past 24 years, his mother, Romaine Bell Thomas, did not shy from the spotlight.

An hour before her son’s announcement, the doyenne of Ward 5 politics and matriarch of its first family received a standing ovation at a D.C. Democratic State Committee meeting.

“Let’s wrap our arms around her and give her a real welcome,” Anita Bonds, the committee chairman, told dozens of party supporters Thursday night at the John A. Wilson Building.

The next morning, Romaine Thomas was in U.S. District Court to watch her son plead guilty to embezzling city funds and falsifying his tax records. By day’s end on Friday, his council office was empty, his name stripped from signs in the Wilson Building.

The spectacle marked not only the end of what prosecutors said was a brazen run of criminality but also quite possibly the end of a local political dynasty, one forged by Romaine and her late husband, Harry L. Thomas Sr.

“They were a couple in politics. They had each other’s backs. Their antennas were everywhere, and they groomed their son,” said council member Vincent B. Orange Sr. , who served two terms as the Ward 5 representative after beating the elder Thomas by 359 votes in the Democratic primary in 1998. Last year, Orange won an at-large seat on the council.

Indeed, in Northeast Washington, the Thomases had been as close to a Kennedy clan as any family could come, and Thomas Jr., 51, was the scion who aspired to greater political heights than the seat he or his father had held for 16 of the past 24 years.

Now, the family’s place in local politics is clouded by a future that almost certainly includes prison for the man still known to many as “Little Harry” or “Tommy.”

In 2010, he had easily won reelection to a second term, with 62 percent of the vote. But like many parts of the District, Ward 5 is changing amid an influx of new residents, and many of them know little about the Thomas family legacy in their corner of the city. Perhaps in a nod to that changing landscape and to his own ambitions, Thomas had said he was considering a future campaign for an at-large seat, a run that would have been a step toward the broader base of supporters he would need were he ever to run for council chairman or mayor.

For now, his only campaign will be one for leniency from the federal judge who is to sentence him in May.

His supporters, still reeling from the resignation and guilty plea, find it hard to imagine Ward 5 without a Thomas in office.

Opinions varied about whether the family could ever return to power. “I don’t know,” said Bonds, whose name is in early chatter about potential Thomas successors. Bonds said she does not know if she will run.

Community activist Jeannette Mobley said when she thinks of the Thomases she thinks of “helping people.”

Could Thomas, who will be sentenced in May, run when he gets out of prison? “He wouldn’t be the first politician to have a comeback,” Mobley said.

Anthony Hood, president of the Woodridge Civic Association, said Thomas’s troubles will become a blip in a long family history. “The things they have done, the impact that they have made will outlive my lifetime,” Hood said.

But some friends said the young Thomas’s fall has sullied a family legacy. “People felt there was a lot of promise for Tommy. He did have some capacity. It’s a shame what’s occurred,” said Craig Pascal, who worked as counsel for Thomas Sr. in the 1990s. “The father was working on behalf of his constituents. There’s a question of whether that was Tommy’s focus.”

Stealing from ward’s youth

According to the U.S. attorney’s office, Thomas began embezzling city funds almost as soon as he took office in 2007, diverting grants to nonprofits for youth sports and other programs and using the money to purchase a luxury sport-utility vehicle, a motorcycle, personal golf trips and clothing. The embezzlement totaled $353,500, according to the plea agreement.

“In the pursuit of this work, I made some poor decisions and acted in ways I simply should not have. I was wrong,” Thomas said in a statement.

That the stolen money had been intended for youth sports programs only made Thomas’s transgression more of a stain on his family’s reputation. His father’s start in community activism decades ago was as a volunteer with his son’s boyhood Little League.

Thomas Sr., who died in 1999, was a high school dropout from Richmond, but he worked two full-time jobs as a federal government worker and as a headwaiter at Bolling Air Force Base to put his wife, son and daughter through college.

After serving as an advisory neighborhood commissioner, chairman of the Ward 5 Democrats and a commissioner of the Alcoholic Beverage Regulation Administration, the elder Thomas won the Ward 5 council seat in 1986.

In office, he built his political name on an annual toy-and-turkey holiday giveaway, forever endearing himself to a core group of Ward 5 constituents and insulating himself from criticism that he did not sponsor substantive legislation. A city street and a recreation center are named for Thomas Sr.

During his last years in office, the elder Thomas was a bit of a curmudgeon. At 72, he made headlines by fighting with a 27-year-old aide who showed up late to work the council member’s annual Christmas toy giveaway. The aide said he’d been “sucker-punched” by Thomas Sr., a former welterweight who kept a pair of gloves given to him by Sugar Ray Leonard hanging on his office wall. Thomas said he was defending himself. “I bopped him,” he said at the time.

Partners in life, politics

Thomas’s partner in politics was Romaine, a native Washingtonian and retired public school principal. She remains active on the state Democratic committee, friends say. She was a one-time Ward 5 campaign coordinator for then-Mayor Marion Barry, who is now a Ward 8 council member.

Together, the couple were heavily involved in national Democratic politics. “They wanted to make sure D.C. was on the map,” Hood said. “They would go to the national party. I never did that.”

When the elder Thomas died in 1999, then-President Bill Clinton and Vice President Al Gore sent condolences to his funeral, which drew more than 1,000 mourners.

The death hit Thomas Jr. hard, he has said in previous interviews. He watched a firefighter, trained as a paramedic, perform CPR on his father to no avail.

Although he had been president of the D.C. Young Democrats and had flirted with a bid for at-large council member in his earlier days, the younger Thomas was better known for his athletic accomplishments than for his political aspirations. He was a football star at Wilson High School, and he involved himself in community activities that often involved athletics.

But almost a decade ago, Thomas set out to restore his family’s place in Ward 5 politics. In 2002, he challenged Orange but lost. A campaign news release at the time said he was “poised to dethrone” Orange, as if Thomas were trying to reclaim a crown.

After Orange ran for mayor, Thomas finally became a political prince, winning the open Ward 5 seat in 2006.

Surpassing his father

Thomas Jr. became the ward boss that his father was and more.

In 2008, he was a “superdelegate” at the Democratic National Convention, and he made national news when he said he would cast his vote for President Obama after initially supporting then-Sen. Hillary Rodham Clinton. At the convention, he gave up his seat on the floor to his mother, whose image was captured on national television.

Starting in 2009, Thomas was one of the council’s most persistent critics of then-Mayor Adrian M. Fenty (D). As chairman of the committee overseeing the city’s parks and recreation agency, Thomas pressed Fenty, dogging him on a number of issues, including the unusual contracting process used on a series of agency contracts.

When Fenty’s attorney general, Peter J. Nickles, first started asking questions about Thomas’s charity fundraising, Thomas dismissed the inquiry as a political vendetta. But Nickles went to court to force Thomas to turn over records, setting the stage for a civil lawsuit filed by Nickles’s successor, Irvin B. Nathan. That led to the federal investigation and the charges filed last week.

In his statement, Thomas said he “let down” his constituents and family. “It is through the efforts of individuals like my mother, a public school principal, and my father, who served as representative of Ward 5 with great distinction, that our community becomes great. It is this legacy of service that I hope to live up to again,” he said.

Orange, who said he knew as soon as he won in 1998 that he would have to fend off an avenging challenge from Thomas Jr., said he was never certain what drove Thomas. “I have no idea if he wanted to be in his father’s footsteps and if it was a sense of entitlement,” he said. “I always thought he’d be just as happy being a coach.”

Staff writer Mike DeBonis contributed to this report.