Not only has David Yassky far surpassed his opponents in fund-raising in the race for the seat representing Brooklyn’s 11th congressional district, the City Council member also has nearly $370,000 in funds left over from an aborted run for district attorney and from his council re-election campaign last year.

Because the money is held in a local committee account, called Yassky for New York, federal campaign finance laws prohibit Mr. Yassky from using it in his high-profile bid to replace the retring Rep. Major Owens. Mr. Yassky, the lone white candidate running in a historically black district, has been accused of being a political opportunist seeking to divide the vote among the three African American candidates.

Mr. Yassky is not saying what he will do with what’s left in the fund, raising questions over whether he is holding onto the cash to mount a future bid for a state or city office if he loses in the Democratic primary a week from today. “That’s a question that will be decided after the election,” a campaign spokesman, Evan Thies, said.

After paying off expenses for Mr. Yassky’s successful re-election bid last year, the committee had $451,553 remaining, campaign filings show. A portion of the money has been refunded to contributors, leaving $369,960 in the account as of July.

Money had been returned to contributors who requested refunds, Mr. Thies said, acknowledging that some of those supporters had then made donations to Mr. Yassky’s congressional campaign. “David is proud to have the support of so many people who believe in his ability to improve New York,” the spokesman said.

Mr. Yassky has nearly $360,000 on hand for his congressional race, according to the most recent filing last month. It is more than his three opponents — Council Member Yvette Clarke, state Senator Carl Andrews, and Chris Owens — have combined.

None of the others has amassed a similar kind of backup war chest. Ms. Clarke owes money from her last council race; Mr. Andrews has a little more than $10,000 in his state account, and Mr. Owens has not run for office since 1989.

Mr. Yassky and Ms. Clarke are seen as the front-runners in a close race. While Ms. Clarke has touted the endorsements of Mr. Weiner and two major health worker unions, Mr. Yassky appeared yesterday with Mayor Bloomberg to announce $600,000 in funding for closed-circuit television systems at two Brooklyn public housing developments.

An appearance that could be interpreted as a last-minute attempt to boost Mr. Yassky’s campaign seemed to backfire, however, when hecklers disrupted the event and a donut dropped from an apartment landed close to where the mayor and Mr. Yassky were standing.

Mr. Bloomberg praised Mr. Yassky’s performance on the City Council but stopped short of endorsing his candidacy for Congress. “I’ve always thought that David Yassky was a city councilman that worked very hard for the city, and I’ll leave it up to the voters who they vote for,” the mayor said.

The hecklers at the event identified themselves as supporters of Mr. Owens, but a spokeswoman for Mr. Owens said they did not work for the campaign. “We were not involved in the incident whatsoever,” the spokeswoman, Amyre Loomis, said.

Among the notable contributors to Mr. Yassky’s earlier races is Rep. Anthony Weiner, who made a personal donation of $250 to Yassky for New York in January 2005, the filings show. Messrs. Weiner and Yassky both worked for then-Rep. Charles Schumer before running for office, but Mr. Weiner has been vocal in his support for Ms. Clarke, who is considered Mr. Yassky’s top rival in the congressional race.

“Anthony has gladly helped David Yassky get re-elected to the City Council, but he is supporting Yvette Clarke for Congress,” a Weiner spokesman, Glen Caplin, said.

Mr. Thies said Mr. Yassky appreciated Mr. Weiner’s earlier support and “looked forward to working with him in Congress.”