President Trump spent much of the past two years promising to bring down energy prices.

Instead, his war with Iran, as well as other policies, drove up the cost of gasoline, diesel and electricity. At the same time his administration worked to thwart efforts to fight climate change, blocking renewable energy investments that could have reduced the country’s reliance on fossil fuels or brought down costs.

On Tuesday, voters’ frustration with soaring energy prices helped propel Democrats to a blowout, with Republicans losing control of the House and the Senate, as well as the governorships of many historically conservative states.

“It’s quite clear that energy and energy affordability in particular played a big role in the electorate’s decision-making last night,” said Hasan Nazar, head of policy at Crux, a clean energy finance company.