ALBANY, N.Y. — Two weeks after officials in two dozen states asked President-elect Donald Trump to kill one of President Obama’s signature plans to curb global warming, another group of state officials is urging Trump to save it.

Democratic attorneys general in 15 states plus four cities and counties sent a letter to Trump asking him to preserve Obama’s Clean Power Plan, New York Attorney General Eric Schneiderman announced Thursday.

The letter was a rebuttal to one sent this month by Republican officials from West Virginia and 21 other states and Democrats from the coal-producing states of Kentucky and Missouri urging Trump to issue a Day 1 executive order declaring the Clean Power Plan unlawful and prohibiting the U.S. Environmental Protection Agency from enforcing it.

The Clean Power Plan aims to reduce carbon dioxide emissions at existing power plants, the nation’s largest source of the pollution, by about one-third by 2030. Opponents say the EPA lacks authority to implement the rules. The plan is already the subject of a legal fight.

Trump has called the science showing climate change a hoax. His choice to head the EPA, Oklahoma Attorney General Scott Pruitt, has sued the EPA repeatedly to stop its climate agenda, including Obama’s sweeping power plant rules. And his nominee to run the Department of Energy, former Texas Gov. Rick Perry, has questioned climate science while working to promote coal-fired power in Texas. But in a television interview this month, Trump said he was “still open-minded” about the science of climate change.

Schneiderman said states like New York are “on the front lines of climate change” and have demonstrated how to cut pollution and emissions while protecting affordable and reliable electricity, creating jobs and growing the economy.

“The Clean Power Plan builds on that successful work and is a blueprint for the critical action needed to fight climate change’s devastating environmental, economic and public health impacts,” he said.

Under Democratic Gov. Andrew Cuomo’s Clean Energy Standard, established this year, 50 percent of New York state’s electricity must come from renewable energy sources like wind and solar by 2030. New York and eight other states are part of the Regional Greenhouse Gas Initiative, a cap-and-trade program that has reduced carbon dioxide emissions from electrical generation in the region by 40 percent from 2005 levels.

In California, the nation’s most populous state, which also signed the letter, the goal is also to have half of its energy from renewable sources by 2030 and a 40 percent reduction of greenhouse gases.

The letter to Trump lists local impacts of climate change from fossil fuel emissions, including drought in California, catastrophic storm surge in New York City, a record deluge on Colorado’s Front Range, high-tide flooding in Virginia and South Florida and diminished shellfish harvest in Oregon and Washington state.

The legal challenge, filed by 27 states that oppose the Clean Power Plan, is before a federal appeals court in Washington, D.C. A decision on the plan could come at any time, but the U.S. Supreme Court has temporarily blocked implementation of the rule until the court challenge is resolved.

Still, even if Trump wants to scrap the plan, it would be a large, time-consuming task.

David Doniger, a climate policy expert with the Natural Resources Defense Council who served on President Clinton’s White House Council of Environmental Quality, said the Trump administration “can’t make it go away unless they go through rulemaking process and unwind it.”

“And that’s a public process, so they’ll have to hear from supporters of the plan,” he said.

Besides New York and California, the letter is signed by attorneys general from the District of Columbia, Hawaii, Illinois, Iowa, Maine, Maryland, Massachusetts, New Mexico, Oregon, Rhode Island, Vermont, Virginia and Washington as well as officials from Broward County and South Miami, Florida, Boulder, Colorado, and New York City.