Councilor John R. Connolly will announce Tuesday that he is a candidate for mayor, striving to topple Thomas M. Menino to become Boston’s first new chief executive in a generation.
Connolly, 39, will hold a rally outside a Boston public school with parents to kick off his campaign, he said in an interview Monday. Menino has not indicated publicly whether he will seek a sixth term, but Connolly is preparing to take on the powerful incumbent.
In formally announcing his run, Connolly will be the first significant candidate to jump into the race, abandoning his council seat. Scores of mayoral hopefuls sit on the sidelines, waiting for Menino’s decision.
In stepping forward, Connolly risks taking the path of three previous councilors who dared to take on Menino and lost both the election and much of their political stature.
“I wouldn’t run if I didn’t think I could win,” Connolly said. “My heart tells me we need to have a serious debate about the city’s future and the city’s schools.”
To overcome long odds, said Connolly, he will try to take a page from President Obama’s playbook, approaching his campaign like a community organizer pushing for better schools. Connolly will try to harness the grass-roots network he has worked to build as chairman of the council’s Education Committee, which held a seven-hour hearing with parents pressing for changes in the teachers’ contract.
“I think you’ll see a massive canvassing effort by us,” said Connolly. “One of the things I’m most excited about is moms of school-age children knocking on doors asking [people] to consider a vote for me.”
The campaign will kick off with a rally at 11 a.m. outside a public school. Connolly declined to name the school, saying he did want to reveal his strategy to the Menino camp.
Menino’s spokeswoman, Dot Joyce, said the administration has never stopped working to improve city schools, “pushing the envelope with innovative practices and game-changing legislation.”
“Mayor Menino and his administration have been focused on young people and education since he became mayor,” Joyce said. “The schools have made great progress under his leadership.”
Menino, 70, must decide by May 13 whether he will file for nomination papers, the first step in launching another campaign. He has been dogged recently by a series of illnesses, which required a two-month hospital stay. For the last two months, Menino has continued his convalescence living at the Parkman House, a city-owned mansion with an elevator.
Asked about Menino’s health, Connolly said he would not make it an issue in the campaign.
“I don’t think it’s relevant,” Connolly said. “He’s clearly up to the job. I take him at his word. It’s not an issue for me.”
The conventional wisdom amid much of Boston’s political establishment is that Menino will run again. But Connolly has decided not to wait. Growing up in Roslindale, Connolly hails from a prominent political family. His mother is chief justice for the state’s district courts, and his father was secretary of state for 16 years and served on the Boston Licensing Board.
Connolly graduated from Harvard College and Boston College Law School. He was elected to the City Council in 2007 and has focused in large part on schools.
Connolly, his wife, and their two young children live in West Roxbury. They are expecting their third child this summer.
“I love Mayor Menino,” Connolly said. “I respect him. His commitment to this city is unquestionable.”
But Connolly said he planned to ask voters “to consider a change toward the future and to bring new energy to City Hall with a real focus on transforming our schools.”
For more than a century, the city charter has concentrated an overwhelming amount of power in the mayor’s office. Menino has maximized that power since taking office in 1993, and he remains popular among residents.
Maura Hennigan, the former city councilor, challenged him in 2005. Hennigan said she hired her campaign manager from out of state because she feared the mayor’s influence. After announcing her run, she said, fund-raising froze because city workers, developers, the nonprofit community, and others political donors remained loyal to the incumbent.
Hennigan recalled walking down the sidewalk and seeing people cross the street because they did not want to be seen with her.
“I give John Connolly a lot of credit, because he is saying he’s all in,” said Hennigan, who is now clerk magistrate for the criminal division of Suffolk Superior Court. “What people have to understand is it’s a very small town.”Andrew Ryan can be reached at email@example.com. Follow him on Twitter @globeandrewryan.