Subsidizing nuclear power to fight climate change is one thing in liberal states like New York and New Jersey. It's quite another in the natural gas bastions of Pennsylvania and Ohio.

Drillers and gas-fired power plant operators are girding to fight measures to save money-losing reactors in the Keystone and Buckeye states, saying they have learned from past defeats and are better positioned to win.

The looming debates are a key test of how far lawmakers in shale gas country are willing to go to fight climate change. Four left-leaning states have already approved bailouts for reactors, in step with aggressive targets to replace coal and gas with clean energy. This time fossil-fuel proponents are fighting on their home turf.

"Natural gas is very, very strong" in Pennsylvania, said state Sen. Ryan Aument, who supports subsidizing reactors. "Those interests are well represented."

In Pennsylvania, a Republican lawmaker introduced a bill recently to support the state's five plants, owned by Exelon Corp., FirstEnergy Solutions and Riverstone Holdings LLC's Talen Energy Corp. Ohio legislators are preparing their own measure.

Time is critical for nuclear plants. Reactors are struggling to stay solvent as the fracking boom has made gas cheap and abundant, pushing down wholesale electricity prices. At least six have closed since 2013, including in New Jersey and Vermont.

FirstEnergy Solutions said it will close its Davis-Besse and Perry nuclear plants in Ohio without subsidies. Exelon needs to order a new reactor core by May for its Three Mile Island plant — site of the infamous 1979 meltdown — making it critical for lawmakers to pass legislation this spring, Chief Executive Chris Crane said on call with analysts last month.

New York became the first state to throw reactors a lifeline in 2016, followed by Illinois, New Jersey and Connecticut. In each case, fossil-fuel generators fought back, saying the bailouts were an intrusion into free markets and would drive up electricity prices. But all four states have aggressive clean-energy targets, and without reactors they would need to rely more heavily on power plants fueled by coal and gas.

"That's what resonated a lot with lawmakers in New York, Illinois and New Jersey," said Timothy Fox, vice president at ClearView Energy Partners LLC. "That argument may not be as strong in states like Pennsylvania and Ohio."

Efstathiou writes for Bloomberg News.