They clashed over increasing the gasoline tax to pay for public transportation. They debated whether Boston City Hall should be bulldozed or renovated. And they fought for a scant few minutes at the microphone on a crowded stage, trying to succinctly make their case that they should succeed outgoing Mayor Thomas M. Menino.
Eight candidates squared off Wednesday morning in one of the first major campaign forums in the race for mayor, sharing a long table before about 150 spectators at the Boston Society of Architects. A ninth candidate, Councilor Charles C. Yancey, arrived uninvited and sat in the audience, elbowing his way into the conversation.
Ten mayoral hopefuls met again in the evening, sharing a stage at a school in Roslindale to answer questions on education policy. Many more mayoral forums will follow throughout the summer.
The first forums offered a glimpse of how the candidates will interact as competitors and highlighted some philosophical and policy differences.
The sharpest exchange Wednesday morning came during a discussion of two competing proposals on Beacon Hill to tackle transportation funding. Governor Deval Patrick has proposed a major transportation expansion by increasing the income tax and reducing the sales tax. The House of Representatives has approved a pared-down transportation plan that would raise the state gasoline tax.
Several candidates – including Councilors Felix G. Arroyo and Rob Consalvo and John F. Barros – applauded Patrick’s plan. Barros and Arroyo criticized the gas tax as a regressive measure that would disproportionately affect people with lower incomes.
Councilor Michael P. Ross said he was deeply concerned about “any presumptive mayor sitting up here who cannot give a full-throated endorsement to the gas tax.” Describing the gas tax as regressive is incorrect, he said.
“We want people to go on public transit,” Ross said, adding that higher gas prices can encourage more people to take the bus or subway.
Barros shot back that not every neighborhood has equal access to public transportation and that some residents have little choice about relying on their own car.
“We’ve got to stay away from acting like everyone’s Boston is the same Boston,” Barros said.
Charlotte Golar Richie reminded the audience of the realities on Beacon Hill. “The question is, ‘What can you get done?’ ” said Richie, a former state representative. “The gas tax would not be my favorite, but it’s one we could get through [the Legislature].”
That sparked a feisty response from Councilor John R. Connolly, who said he supported the governor’s plan and described the gas tax option as surrendering to the status quo on Beacon Hill.
“We need to change that attitude,” Connolly said. “We need a mayor who is going to be in the transportation debate, not sitting it out, saying, ‘That’s the state.’ ”
Candidates differed on what should happen to City Hall, a building beloved by many architects in the audience, but loathed by much of the public.
Arroyo said he would be open to the idea of building a new City Hall, as long as the replacement is accessible to the public.
Richie and Representative Martin J. Walsh both said that bulldozing City Hall would be low on their priority list.
William J. Walczak suggested that Hanover Street could be extended from the North End to open up Government Center, and that the backside of City Hall would be a good spot for a Boston history museum.
During the evening forum, some candidates sparred over the hot-button issue of lifting the cap on charter schools. Critics say the schools take money away from public schools.
Suffolk District Attorney Daniel F. Conley voiced support for lifting the cap, citing research showing that most city charter schools are high-performing.
He said failing to lift the cap “would be the equivalent of us saying to Apple, you make the best smartphone, but we’re not going to allow you to distribute it to everyone who wants to buy it.”
Some of his rivals disagreed.
“I don’t believe now is the time to raise the cap on charter schools,’’ Arroyo said. “In fact, I think now is the time to double down on public education.”
Yancey sounded a similar note, declaring that the system as a whole “deserves more investment, not disinvestment.”
Consalvo, who also opposes lifting the cap, called for “full funding to help kids with special needs,” especially in low-performing schools.
The district attorney, however, had a strong ally on the charter question in Connolly, who repeatedly called for lengthening the school day.
Michael Levenson of the Globe staff contributed to this report. Andrew Ryan can be reached at email@example.com.