Iowa’s junior U.S. Senator Joni Ernst says she now has it in writing from the Environmental Protection Agency it will uphold the Renewable Fuel Standard. She got the news late Thursday night.

The Republican says she received a letter from EPA administrator Scott Pruitt pledging to support the RFS, which mandates the use of biofuels in gasoline. The Trump administration became the target of a heavy lobbying effort from Iowa elected officials and farm groups after it was reported the EPA would scale back the RFS. Ernst says she’s relieved.

“This is a huge victory for our farmers and for manufacturers, and to get this assurance in writing was key,” she says.

Ernst says she is satisfied with the Administration's position, for now.

“I take this as a win," she says. "Of course, we would like to see that greater volumes are set, but we’re going to take this as a win.”

Ernst says she will now support President Trump’s nominees for key posts in the EPA, including the man who will be in charge of enforcing the RFS.