For Brian Beffort, the sustainability manager of Washoe County, Nev., the federal government’s commitment to fighting climate change has been basically a bonanza.

He’s been on the job for 15 months and already the county, which includes Reno, is expecting money to start flowing from a $156 million statewide grant he helped clench that can pay for rooftop solar panels for low-income residents. Other federal programs will fund urban reforesting and map Reno’s hottest neighborhoods. Mr. Beffort is also waiting to hear whether the county will receive a multimillion-dollar federal grant to reduce air pollution.

So much money is being offered, “it’s hard to keep up,” he said. “This is a great time to be in sustainability and climate action.”

The Biden administration’s push to fight climate change has sprinkled billions of dollars across America for major projects, such as building new transmission lines for electric power, and for smaller ones, like planting trees. The centerpiece of the president’s effort, the Inflation Reduction Act, is injecting more than $370 billion into programs aimed at helping the United States cut greenhouse gas emissions by an estimated 40 percent below 2005 levels by the end of this decade.

But in this election year, officials in Nevada and beyond who are facing new threats from climate change are wondering whether the flow of assistance will last.

It’s unclear how much the federal funding for climate projects is lifting support for President Biden. In Nevada, a battleground state, Mr. Biden’s presumed Republican rival, former President Donald J. Trump, holds a significant lead in the polls. Mr. Trump also leads in Arizona and Georgia, other election battlegrounds where Biden administration climate policies have helped bring billions of dollars in new investments.