Sen. Michael Bennet is arguing that the Republican tax bill could dim the energy behind wind and solar development in states that are plugged in, such as Colorado.

The Democrat from Denver signed a letter to leaders of Senate Finance Committee and House Ways and Means Committee to preserve wind a solar tax credits in their plan to overhaul the tax code, reportedly to spur business growth and give Americans some tax cuts.

“My office has been contacted by many small business owners who depend on these credits-people like Evelyn, a small business owner in Fort Collins, Colo., whose company employs 30 people,” Bennet said during a Tuesday press conference. “Her business is dependent on solar and wind energy, and she’s worried she would have to reduce her workforce if those credits were rolled back.”

While the bill undercuts such investments as support for wind farms and electric vehicles, it would give fax breaks to more traditional energy sources such as nuclear power and fossil fuels.

The Trump administration is intent, however.

“I would do away with these incentives that we give to wind and solar,” Scott Pruitt, the chief of the Environmental Protection Agency, said two months ago. “I’d let them stand on their own and compete against coal and natural gas.”

Bennet signed with letters with fellow Democratic Sens. Ed Markey of Massachusetts, Sheldon Whitehouse of Rhode Island, Brian Schatz of Hawaii, Ben Cardin of Maryland, Amy Klobuchar of Minnesota Jeff Merkley of Oregon, Tom Udall of New Mexico and Richard Blumenthal of Connecticut.

They allege that if the Republican majority strikes renewable energy provisions in the tax bill it would “devastate clean energy deployment and job growth.”

Democrats say 360,000 Americans are employed in the wind and solar energy business, a number that’s expected to grow to 500,000 over the next three years.

The credits have enjoyed bipartisan support in the past, according to Bennet.

“That’s why it makes absolutely no sense to me why this Congress would end years of agreement and risk undoing these credits,” he stated. “It would have irreparable effects on the economy in Colorado and make this terrible Republican tax bill even worse.”

The American Wind Energy Association released a report this year that said wind alone could grow its Colorado job base from 14,800 workers to 22,900 by the end of 2020.

Wind industry jobs nationwide are expected to hit 248,000 in 2020, up from just 100,000 in 2016, the report states.

According to the Colorado Energy Office, the state ranks 11th nationally for installed solar capacity with 454 solar companies that collectively employ about 6,000 people. Colorado saw more than $510 million in investments in solar operations in 2016 alone.