Shaun Donovan, a former housing secretary and budget director under President Barack Obama, filed paperwork on Monday to run for mayor of New York City.
Mr. Donovan was housing secretary from 2009 to 2014 before becoming budget director until Mr. Obama left office. During his time at the White House, he worked on expanding access to health care, an administration priority, and helped coordinate efforts the help the city recover after Hurricane Sandy.
For years, speculation has surrounded Mr. Donovan’s interest in a City Hall bid. His background as a member of Mr. Obama’s cabinet and his familiarity with the city, as housing commissioner when Michael R. Bloomberg was mayor, could give him credibility among voters.
“I think New Yorkers will be looking for a candidate who puts public service, and making the city work for everyone, above politics,” he said in an interview on Monday. “I think that makes me unique.”
For all of Mr. Donovan’s experience, he faces steep hurdles.
He is not well known outside policy circles in New York and Washington, and he has never run for office before. He also has not formally begun to raise money or assemble a staff, putting him well behind other, more established candidates.
Mr. Donovan, 54, is also a white man, a demographic already well represented in the race so far.
Of the three leading candidates in terms of name recognition and money raised, all are men, and two are white. They include Eric L. Adams, the Brooklyn borough president, who is black, and the city comptroller, Scott M. Stringer, and the City Council speaker, Corey Johnson, who are white.
Asked about his credentials to lead such a racially and ethnically diverse city, he talked about his experience trying to help people of all backgrounds.
“My life’s work was shaped by seeing New Yorkers living on the street and getting left behind in the city,” Mr. Donovan said in the interview. “Look at what happened in the Obama administration under my leadership.”
He specifically cited the housing agency’s efforts to combat homelessness, which he said had been reduced “dramatically” on his watch. “Veteran homelessness, we cut in half,” he added.
“I think the current occupant of the White House has made not just New Yorkers but people across the world miss Barack Obama more than they ever have,” Mr. Donovan said, without identifying President Trump by name.
Others who are running for mayor include Loree Sutton, the former leader of the city’s Veterans’ Services Department under Mayor Bill de Blasio, and Dianne Morales, who runs a nonprofit social services agency in the South Bronx.
Several mayoral candidates have pledged not to accept campaign donations from the real estate industry as concerns continue to grow about New York’s affordability and an increase in gentrification.
Mr. Donovan, an architect by training, was noncommittal about whether he would accept such donations. He declined to provide specifics about the “tactics of the campaign” beyond saying that he would raise money to help pay for it.
Mr. Donovan first emerged as a potential candidate for mayor in 2017, when Bradley Tusk, a former special adviser in Mr. Bloomberg’s administration, tried unsuccessfully to recruit him to challenge Mr. de Blasio.
Mr. Tusk, who now runs a political consulting firm, Tusk Strategies, believes that Mr. Donovan would have a hard time winning the coming race.
“He has no name ID,” Mr. Tusk said. “It’s hard to see how marshaling institutional support would really make a difference.”
“Is he a top-tier candidate?” Mr. Tusk said. “No. Is there a clear viable path? Not really. Would he be good at the job, yeah.” (Mr. Tusk said that one of his associates was informally advising Mr. Johnson.)
The Rev. Al Sharpton, a civil-rights leader whose support many of the Democrats running for mayor are seeking, said that Mr. Donovan had called him on Sunday to inform him of his plans.
“The Obama thing is going to work for him, but the Bloomberg thing is going to be questioned,” Mr. Sharpton said.
By the time Mr. Bloomberg left office after 12 years, the issue of income inequality had become weighty enough to help pave the way for the election of Mr. de Blasio, Mr. Bloomberg’s ideological opposite. (Bill Hyers, who managed Mr. de Blasio’s first mayoral run, is now a senior adviser to Mr. Donovan; Rick Fromberg, who managed Mr. de Blasio’s re-election campaign, is also working with him.)
“I’m proud that when given a chance to serve the city, I stepped up to do that,” Mr. Donovan said.
“Mike and I didn’t agree on everything,” he added, while saying, “I think my alignment with President Obama, whether it’s criminal justice or a range of other areas, is very, very strong.”
As for another white man jockeying to lead a city whose racial makeup is increasingly nonwhite, Mr. Sharpton said it would undoubtedly be an obstacle for Mr. Donovan, although not an insurmountable one.
Even when Mr. Donovan was in Washington, Mr. Sharpton said, “he always kept in contact.”
“I think he is a candidate that should be taken seriously,” he said.