A liberal political activist group connected to the chairman of the Democratic National Committee, Howard Dean, is trying to persuade Assembly Speaker Sheldon Silver to debate his two Democratic primary challengers next month.

The 64-year-old legislator, a trial lawyer by trade who has not faced a primary opponent for his state Assembly seat in more than two decades, does not appear to be interested. A campaign spokesman suggested that the speaker might be willing to debate his opponents, an attorney from the East Village, Luke Henry, and a former AIDS awareness organizer from the Lower East Side, Paul Newell, at a later date closer to the September election.

“We fully expect over the course of a campaign that there will be many opportunities for the speaker to talk about his record,” a spokesman for Mr. Silver’s campaign, Jonathan Rosen, said. “But for now, the speaker is going to continue to focus on his work as a legislator, which means delivering results for Lower Manhattan.”

The group seeking to organize the debate is Democracy For New York City, a nonprofit political action committee affiliated with Democracy for America, which was founded by Dr. Dean after his run for president in 2004.

“If Sheldon Silver wants to avoid a frank discussion of the issues facing Lower Manhattanites, then he should come out and say it,” Mr. Newell said.

Mr. Silver, who has been speaker since 1995, has broad support among his legislative colleagues, a campaign account that dwarfs the money raised by his challengers, and deep roots in his Lower East Side community.

The speaker is not sitting idle: He’s hired a consulting firm to assist his campaign and he is looking to broaden his base beyond his Jewish constituency in Lower Manhattan. The Observer yesterday noted that Mr. Silver bought a $500 ticket to a fund-raiser hosted by the Stonewall Democratic Club of New York City, a gay political group.