BOSTON — House Speaker Ron Mariano stood before a roomful of business leaders at the Fairmont Copley Plaza, surrounded by coffee, croissants, and mini quiches, and called the ballot question to cut your income tax "just such nonsense."

"It's insulting to me as someone who follows public policy that they think that they can solve problems that way," Mariano told the Greater Boston Chamber of Commerce crowd on Thursday. "I don't know if you notice a little bit of anger in that because I'm a little bit just tired of this."

The ballot question, backed by the Massachusetts Opportunity Alliance and a coalition of business groups including the Massachusetts High Technology Council and the Pioneer Institute, would lower the state income tax rate from 5% to 4% over three years, dropping to 4.67% in 2027, 4.33% in 2028, and 4% beginning in 2029.

Mariano didn't just trash the ballot question. He threatened that if voters approve it, the Legislature would be forced "to make significant budget cuts to services and programs that our residents rely on."

Then came the kicker: it "could also force the Legislature to consider the need for new sources of revenue."

Translation: vote to cut your income tax, and Beacon Hill might raise taxes somewhere else.

In the same breath that he called the ballot question nonsense, Mariano left open the possibility of a compromise with the pro-tax-cut forces, suggesting there could be longer-term solutions that addressed their underlying complaints.

So the campaign is insulting, but he's open to chatting about it.

The mixed messaging came just hours after the Massachusetts Opportunity Alliance rolled out new polling data showing that classroom teachers support the tax cut, a direct shot at the Massachusetts Teachers Association, one of the ballot question's most vocal critics.

MTA president Max Page dismissed the data as a "push poll" and said his union's board unanimously opposed the ballot measures. "They are so clear because they know the damage this will do," Page said.

Governor Maura Healey has also expressed concerns about the revenue impact, though she has stopped short of Mariano's language.

The business groups pushing the question say Massachusetts is driving residents and companies out of the state with high costs. They point to years of population loss and a tax burden made worse by the 2022 "millionaires tax" surtax that added a 4% surcharge on income above $1 million.

Mariano can call it nonsense from the ballroom of a Back Bay hotel. The unions can sue. Healey can wring her hands. But if the ballot question survives the legal challenges, Massachusetts voters will decide in November whether they want to keep paying 5% or cut it to 4%.

The last time voters were asked about the income tax rate, they voted to cut it. Beacon Hill ignored them for years.