D.C. Council members Muriel Bowser and Phil Mendelson speak at a council meeting. (Sarah L. Voisin/The Washington Post)

D.C. Council member Muriel Bowser will announce Saturday that she is launching a run for mayor, according to campaign advisers, making her the first to officially enter the 2014 race.

Bowser, 40, has represented Ward 4 as a Democrat since 2007and has been much discussed in recent years as a potential citywide candidate. Endorsed by Adrian M. Fenty (D) to fill his council seat after he became mayor, Bowser has followed a similar path, focusing on constituent services and quality-of-life issues.

The announcement is set for Saturday morning at Bowser’s childhood home in the North Michigan Park neighborhood, said a campaign adviser who was not authorized to comment publicly.

In an interview Monday, Bowser acknowledged that “there will be an announcement” Saturday, but she declined to discuss its nature. Two people involved in the campaign but not authorized to comment publicly confirmed that she will announce a mayoral run.

Several council members, emboldened by Mayor Vincent C. Gray’s early missteps and the ongoing federal investigation into his 2010 campaign, have made moves toward entering the race. But barring a surprise announcement from a rival this week, Bowser will be the first to formally declare her intentions.

Tommy Wells (D-Ward 6) launched an exploratory campaign in January and has said he is likely to officially enter the contest this spring. Jack Evans (D-Ward 2) also has said he plans to enter the race, and David A. Catania (I-At Large) has pondered running.

Of the council members said to be considering a run, Bowser is the only woman, only African American and only District native. After winning the 2007 special election to fill Fenty’s Ward 4 seat, she was reelected in 2008 and 2012.

Gray (D) has declined to discuss whether he plans to seek reelection, though he has privately told advisers he is considering a run.

Speculation that Bowser might pursue citywide office next year was stoked during her last campaign, for which she raised nearly $356,000to defeat only token opposition — a show of fundraising strength. Evans, who has long eyed citywide office, raised about $370,000 for his unopposed race last year.

Early in her term, Bowser embraced the Fenty association — not only backing him on virtually all of his political initiatives but also choosing the same shade of green for her campaign signs that he used for his council and mayoral runs.

But after Fenty’s 10-percentage-point loss to Gray in the 2010 Democratic primary, Bowser moved to distance herself politically from the former mayor, who had become divisive in the black middle-class neighborhoods that make up the heart of Bowser’s ward. The green color scheme, for instance, turned yellow.

Gray’s political morass and Bowser’s easy 2012 victory, however, have made the Fenty association less troublesome today.

A Washington Post poll conducted in July found that the public’s opinion of Fenty’s performance as mayor has improved significantly since he left office. About one-fourth of those polled who voted for Gray in the 2010 primary said they would vote for Fenty instead.

The poll, however, found that none of the potential mayoral candidates on the council was particularly well known citywide or well positioned to seek the mayoralty.

More people had favorable (23 percent) than unfavorable views (11 percent) of Bowser, but two-thirds of D.C. residents (66 percent) said they had no opinion of her. Many of the other potential contenders were widely unknown, including Wells (62 percent) and Phil Mendelson (55 percent).

Backers said they think that Bowser can harness Fenty’s enduring popularity in the white-majority portions of the city while rebuilding relations with black voters he alienated as mayor. Bowser hails from a politically active family with deep roots in Ward 5, the heart of working-class Washington, and represents middle-class Ward 4, which traditionally has the city’s highest voter turnout.

In speeches at an August birthday fundraiser and at her January swearing-in, she has sought to portray herself as able to reconcile divisions of race, class and geography. “We want to be proud of where we live and we want to have the opportunity to participate in the bountiful growth that is the District of Columbia — and like you, we don’t want to be left behind,” she said in January.

According to the Post poll, Bowser is better known among African Americans than whites, although a higher proportion of black residents holds an unfavorable impression of her than white residents do (15 percent vs. 6 percent).

Several key Fenty advisers, including campaign chairman Bill Lightfoot and strategist Tom Lindenfeld, are likely to reprise those roles for Bowser. Both declined to comment ahead of the Saturday announcement.

The rollout has shades of Fenty’s successful 2006 run: He was the first to enter that race, kicking off his run in front of his childhood home in Mount Pleasant.

One significant difference is that the District’s 2014 election cycle will be the first mayoral race to feature an April primary. Previously, primary elections took place in September.

Evans, reiterating Monday that he intends to run for mayor, said he did not see a particular advantage to being the first to enter the race. Candidates can build support for a run, he said, without launching a formal campaign.

“I think that everyone has their own timetable,” he said. “The value of having a campaign is being able to raise money.”

Scott Clement contributed to this report.