With City Councilor Tito Jackson’s entrance into the 2017 mayoral race, a question looms: Will black voters unite behind him or will they stick with the candidate they helped elect in 2013, Mayor Martin J. Walsh?

Boston’s black leaders have been yearning for the chance to run the city since former state representative Mel King made it to the November election in 1983 and lost. But low turnout, lapses in funding, and an inadequate ground game have plagued the chances of many candidates of color.

Now Jackson, who announced his campaign for mayor on Thursday, is hoping to realize a dream of becoming the first viable African-American challenger on the November ballot since King. If that happens, some say the black vote will split between beloved progressives — Walsh, the son of Irish immigrants, and Jackson, the adopted son of Grove Hall activists.

“This is an opportunity to make history in the city of Boston,’’ said the Rev. Miniard Culpepper, a Dorchester pastor who supported Walsh’s 2013 opponent, John Connolly, before becoming an ally of the mayor.

But now, Culpepper said, he’s supporting Jackson’s “history-making bid’’ because “this is much bigger than Tito.’’

Indeed, a Walsh-Jackson match-up poses an interesting prospect for some black voters in the city.

“Communities of color are going to decide the next mayor of Boston,’’ said activist James Hills, who lives in Mattapan and is neutral so far in the race. “The determining [questions] are: Will the older Bostonians see this as the last hoorah and a way to move from the debacle of 2013? And where will the young adult votes go?’’

But Kim Janey, a public education advocate who announced her intentions to run for Jackson’s council seat, said a Jackson-Walsh race will be great for the city.

“I’m excited,’’ Janey said. “[Jackson] will certainly have support in the black community. But people don’t just vote along racial lines.’’

Hyde Park resident Rickie Thompson said he wants to see the councilor make it all the way.

“But in a sense I was concerned that it might not turn out good,’’ said Thompson, a member of the East River Street Neighborhood Association. “The only way he can win is if he gets a concentrated support behind him, as opposed to the last time when they had 12 people running.’’

Black residents can recall the divisions that haunted the crowded 2013 mayoral primary and a failed effort to rally behind a single African-American candidate, Charlotte Golar Richie.

As Connolly and Walsh advanced to the general election later that year, black elected leaders — including Jackson — lined up in support of Walsh.

Walsh, at another event at police headquarters Thursday, said he welcomes anyone running for mayor, but he added that he will stay clear of addressing politics until candidates officially file papers in the spring. Mayoral candidates must submit 3,000 signatures by May 23.

He said he’s focused on his job, including working on next year’s budget, improving city schools, and working on other city initiatives.

Still he appeared to take a slight dig at Jackson by at least twice lumping his name with a relative unknown, Mary Franklin, who announced her intentions run for mayor last year.

As for the black community, Walsh told the Globe earlier in the week he’s had some “difficult discussions’’ about the work that he’s done in his three years in office.

“I do not take anything for granted and I certainly am not going to take the black community for granted,’’ he said. “I have many friends in the black community. We’ve done a lot of work in all the neighborhoods.’’

At his announcement in Dudley Square on Thursday, Jackson said that his time has come to lead Boston, and he criticized the mayor on a number of fronts, including gender equity and a building boom that is pricing out residents from their homes.

“Our time has come to have a Boston that has a mayor . . . who will not only talk about issues of race, but will do something to close disparities in unemployment and create more jobs for all neighborhoods,’’ Jackson said to applause.

Walsh has made inroads in the black community since taking office in 2014 with focuses such as diversifying his Cabinet, launching race dialogues, and targeting struggling neighborhoods for revival.

But he has been criticized for moving too slowly on issues that black Bostonians say matter, such as addressing a racial crisis at Boston Latin School, connecting the black community to union jobs, and ensuring that black residents are getting their fair share of construction jobs.

“Those are the things that he needed to move faster on,’’ said state Representative Russell Holmes, a close friend of Walsh’s who was at Jackson’s announcement in Dudley Square.

Preston Williams, a board member of Massachusetts Association of Minority Law Enforcement Officers, said Walsh has made progress in the black community, but Jackson still has a chance.

“If Tito sends the right message, he’s got a chance of winning this,’’ he said.

Other key black leaders downplayed any divide, saying a race between Jackson and Walsh would highlight the visions both men have for the city and the direction they want to take it.

“Black people are much more astute than letting this be a wedge,’’ said Darnell Williams, who heads the local Urban League. “This is going to really be about what is best for the city’s interest.’’

Joyce Ferriabough Bolling, a political consultant from Roxbury, said that as a native son of the neighborhood, Jackson has done well to represent his district, which includes Roxbury, the South End, and sliver of Dorchester.

“There will be a natural tendency for folks of color to support one of their own,‘’ she said.

For example, she said, many political observers knew Walsh was going to take a good chunk of the areas in Dorchester he represented, and he clearly split the Irish vote with Connolly in 2013.

“In the end it’s a numbers game,’’ Ferraibough said.

Chuck Turner, who long represented Roxbury, said he was inspiring to see “a black man stand up’’ and declare his candidacy to lead the city. Race and the black vote will always be factors in Boston, he said.

“The question is how will this play in the white community,’’ he said. “Are white people going to vote for a black person they think can help this city?’’