Gov. Tom Wolf’s plan to dramatically boost education funding by raising the income tax rate was cheered Wednesday by advocates who have long called for Pennsylvania to step up its investment in public schools and narrow gaps in resources between wealthy and poor communities.

But Wolf’s budget proposal wouldn’t just drive dollars to poorer districts like Philadelphia. It would help wealthier districts, too. Lower Merion, for instance, would see a 60% increase in state aid. Radnor would get a 65% boost, while West Chester would net a more than 85% increase.

Those percentage increases are greater than the 22.5% granted to much larger Philadelphia, which relies more heavily on state aid. But Philadelphia would get an additional $262 million, compared with $2.5 million for Lower Merion.

The Democratic governor’s proposal faces opposition in the GOP-led legislature, where lawmakers have objected to his income tax plan. The Wolf administration says the plan wouldn’t affect two-thirds of Pennsylvanians, but it would nearly double the tax rate paid by higher earners. Senate Republicans on Wednesday called the proposal “dead on arrival.”

The plan casts new light on the long-running debate over how Pennsylvania funds public education — among the myriad issues that will now go through months of hearings and negotiations as lawmakers seek to pass a budget by June 30.

The increases slated for schools are part of a massive redistribution of existing state aid proposed by Wolf, coupled with an additional $1.3 billion in spending to ensure that no district loses money in the process.

Wolf is proposing to run all of the state’s main subsidy to public schools through a “fair funding” formula Pennsylvania enacted in 2016. The formula, which is currently used to distribute 11% of state aid, is intended to direct funding to communities with greater needs — adding money for students living in poverty and other factors, and taking into account a district’s ability to raise revenue through local taxes.

“We will be able to fully and fairly fund every school, in every school district, in every part of the commonwealth,” Wolf said Wednesday in his budget address.

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But it also reflects a district’s general enrollment. Because Pennsylvania has long neglected to account for enrollment shifts in distributing school funding, some growing districts would see a big boost under Wolf’s plan, even if they are relatively well-off.

Meanwhile, districts that have lost students wouldn’t see funding cuts; Wolf’s budget includes $1.15 billion to offset those losses.

“That’s been the issue: How do you put all that money through the formula, which for the most part everyone agrees with, without devastating those districts?” said Mark DiRocco, executive director of the Pennsylvania Association of School Administrators.

Yet, the proposal also highlights questions around funding education in a way that is both equitable and adequate. While many advocates welcomed Wolf’s plan as a sweeping investment in schools — in a state that has relied heavily on local revenues to fund public education — some said it also revealed the problem with relying on the funding formula alone, without evaluating whether certain districts already had enough resources for educating students.

Not assessing which school districts have enough money — and which are most lacking — is “an irresponsible use of tax dollars,” said Donna Cooper, executive director of Public Citizens for Children and Youth.

Though Cooper credited Wolf’s proposal with sending additional money to districts that have more low-income children, she faulted lawmakers for not calculating spending targets for each district.

A recent analysis prepared for plaintiffs challenging Pennsylvania’s school funding system determined that schools need an additional $4.6 billion to adequately educate students. However, not all schools have equal need: The report commissioned by the Education Law Center and Public Interest Law Center found that some schools already have enough money, including districts like Lower Merion and Radnor.

“There is absolutely a huge need to accelerate additional resources to a lot of school districts,” said Hannah Barrick, assistant executive director of the Pennsylvania Association of School Business Officials. But “is this the best pathway? I’m not sure about that yet.”

In addition to enrollment increases, Pennsylvania’s funding formula accounts for a school district’s tax effort: If a district taxes residents at a relatively high rate, that can trigger more state funding, even if a district is relatively wealthy, Barrick said.

That appeared to be a factor in the York Suburban School District, where Wolf’s plan would add $8.6 million — a greater than 300% increase over its previous $2.8 million in aid.

Some of the starker increases are simply a product of the formula’s being fully used for the first time, DiRocco said.

“Initially it’s going to look like some winners and losers. You have to look at this with a long-term lens to see what impact you will have down the road,” he said.

Republican lawmakers quickly criticized Wolf’s plan, which would increase the personal income tax rate from 3.07% to 4.49%. “This proposed budget shows the disdain Gov. Wolf and his Democrat allies have for middle-class families and the small businesses that employ them,” said Jake Corman, the Republican Senate leader.

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Yet, for districts like Philadelphia, Wolf’s plan was welcome news.

“In addition to investing almost $2 billion more in students and schools, and distributing education funds in a more equitable formula, his proposal calls for much needed charter school funding reform and investments in school infrastructure,” Superintendent William R. Hite Jr. said in a statement, adding that the proposal “would have a significant impact on the recurring revenues needed by the district to invest more in classrooms and support the educational success of our students.”

Sen. Vincent Hughes, a Democrat whose district covers both crumbling schools in Philadelphia and state-of-the-art facilities in Montgomery County, said Wolf’s proposal would “finally deal with the issues of equity.”

“The governor’s created a proposal that gets significant funding to districts that have been left out for generations,” he said. And “he does it in a way where no student is harmed.”

Staff writer Kristen A. Graham contributed to this article.