TALLAHASSEE — The Florida governor’s race became a battle over school funding Tuesday, with Democrat Andrew Gillum defending his $1 billion tax proposal and Republican Ron DeSantis promising to steer money from overhead into classrooms.

Flanked by educators, Gillum said his plan to boost the state’s corporate income tax only makes Florida’s big businesses pay their “fair share” and would be softened by federal tax cuts that already favor corporations.

“This is an investment in our future, in our state’s economy and in Florida’s businesses,” Gillum said. “We’re talking about training up the next generation of workforce that will power Florida’s future economy. And simply put, we’re saying that everybody has to pay their fair share.”

Gillum has been under heightened pressure from Republicans and their business allies since GateHouse Florida reported that the Democrat’s proposal is sending shock waves through industry organizations, even as it faces long odds of succeeding in a GOP-controlled state Legislature.

Gillum would boost the state’s 5.5 percent tax on corporate income to 7.75 percent to help raise $1 billion that he would pour into schools, improving per-pupil funding, expanding technical programs and giving teachers a minimum $50,000 starting salary.

DeSantis unveiled his own billion-dollar proposal Tuesday — built on redirecting school administrative costs into the classroom. DeSantis would require that 80 percent of state public school dollars go to classrooms, up from the level of about 74 percent, which he said was reached in 2016-17.

DeSantis’s campaign says that increase would yield almost $1.4 billion more for schools.

The 80 percent proposal was part of an education package the Republican unveiled Tuesday that aligns with his party’s support for private-school vouchers. DeSantis is pledging to expand the state’s tax credit scholarship program, give parents more school choice options and reward primarily high-performing teachers.

DeSantis also called for an audit of the state’s Department of Education and an online database in each school district tracking spending — measures that he said could bolster the push for more dollars in classrooms.

Pushing back against the Common Core curriculum standards that had been advanced by President Obama and supported by former Florida Republican Gov. Jeb Bush, DeSantis said he was wary of “one-size-fits-all” evaluations. He wants a review of these testing measures and would expand the emphasis on civics and constitutional principles in schools.

Gillum and DeSantis, though, do seem to agree on Florida schools bolstering their technical and apprenticeship programs to meet the needs of students not inclined toward college.

While DeSantis said little publicly Tuesday about his education platform, Gillum called a news conference to defend his corporate tax hike after a steady drumbeat from Republican-allied organizations that warned it would rock the state’s economy.

Gillum cited President Donald Trump and the Republican-led Congress’ support for a massive tax cut package last December that is helping corporations save billions of dollars.

“The argument they made is that these tax breaks were going to filtrate down to everyday working people ... suffering in this state and all over the country,” Gillum said. “The truth is that 44 percent of working families say they cannot make ends meet.”

He also disputed claims that increasing taxes on businesses will force consumer prices up.

“The truth is, the corporate tax rate in the state of Georgia is higher than that in Florida. And the 99-cent menu is the same in both our states,” Gillum said.

Republicans swung back — again.

“No matter how he tries to spin this, raising $1 billion in taxes would be a disaster for hardworking Florida families,” said Meredith Beatrice, a Florida GOP spokeswoman.