Seven of the twelve candidates running for mayor stepped off the campaign trail on Friday and spent several hours inside City Hall at a hearing on the Suffolk Downs casino proposal.

Two questions stemming from the proposal have lead to some of the sharpest exchanges of the race: Should Boston have a casino? And should the referendum on the casino take place only in East Boston or citywide?

Suffolk Downs has asked for the referendum to take place on Nov. 5, the same day voters go to the polls to choose a new mayor. The Sept. 24 preliminary will winnow the field to two candidates.

Suffolk District Attorney Dan Conley and Codman Square Health Center co-founder Bill Walczak have raised concerns about the benefits a casino would bring and both have demanded a citywide vote. Walczak has been the most forceful candidate on the issue, referring to the casino proposal as a “con job on Boston,” while Conley, who has questioned the legality of a neighborhood-only vote, argued that Boston is not simply a “confederacy of neighborhoods.”

But the second question – citywide vote or East Boston-only – has also led to some division within the 13-member council, which has five of its members running for mayor. City Council President Stephen Murphy, who is running for reelection to the council, has said there is little appetite among his members for a citywide vote.

The Friday hearing on the casino proposal and the referendum showed that was true: District 5 Councillor Rob Consalvo (Hyde Park), District 8 Councillor Michael Ross (Mission Hill) and City Councillors At-Large Felix Arroyo and John Connolly back their colleague, District 1 Councillor Sal LaMattina, who argues that the proposal will provide infrastructure upgrades and other benefits to his East Boston neighborhood.

Consalvo, Ross, Arroyo and Connolly are all running for mayor. Charles Yancey (Dorchester/Mattapan), who is running for mayor and for reelection to his District 4 council seat, also put in an appearance at the hearing; he supports a citywide vote, with weight added to an East Boston-only vote.

At the hearing, LaMattina raised the specter of a citywide vote in which the city votes for a casino, while East Boston votes against it. “Is that fair to my neighborhood?” LaMattina said. “I don’t think so.”

Looking in the direction of District 6 Councillor Matt O’Malley (Jamaica Plain) and District 7 Councillor Tito Jackson (Dorchester/Roxbury), who both support a citywide vote, LaMattina asked how councillors would feel about the entire city voting on development projects in Roxbury and South Boston.

O’Malley called said that argument deployed “incongruous logic.” A resort casino cannot be equated with a roof deck in South Boston, he said.

City Councillor At-Large Ayanna Pressley backed a neighborhood-only vote. “To say I’m not a fan of gaming would be the understatement of the year,” she said. But, she added, she did not want to marginalize East Boston residents by opening up the vote to the rest of the city.

District 3 Councillor Frank Baker appeared undecided on the scope of the referendum; he said he supports the casino proposal itself. Baker noted he would live within a 10-mile radius of the casino, and Dorchester Avenue will see the “social ills” of a casino. “I wish the councillors had some sort of say in this agreement,” he said of the agreement hammered out between the city and Suffolk Downs. “If they had just asked our opinion, it would’ve been nice.”

After testifying, Walczak acknowledged that a citywide vote was unlikely. He laced into the City Council, saying “they’re going along with the con.” “The only way to stop this casino is to vote for me,” Walczak said.

State Rep. Carlo Basile, an East Boston Democrat, testified in favor of a neighborhood-only vote, saying he was insulted that mayoral candidates were using the vote as a “political football.”

He was soon followed by Alice Christopher, an 84-year-old East Boston resident, who furiously wagged her finger at O’Malley and Jackson. “Where was the rest of Boston” when the neighborhood was fighting the expansion of Logan Airport, she said.

Christopher, who managed the “Little City Hall” in East Boston for Mayor Kevin White, received a round of applause from the crowd inside the City Council’s chamber after she finished her fiery testimony.

Stepping outside the chamber, Christopher was seething at the councillors. “You have no right to take that vote away from us,” she said.

Basile, who stood next to her, grinned. “I can’t wait for you to announce me for reelection,” he said.