House Republicans call their plan for tackling climate change “realistic.” Right-wing think tanks call it a “Green New Deal Lite.” House Minority Leader Kevin McCarthy (R-Calif.) and other top House Republicans find themselves at odds with a series of conservative lobbying groups in Washington over what to do about rising global temperatures.

In the face of shifting poll numbers, top House Republicans are hoping to turn over a new green leaf with a fresh package of climate bills that addresses climate change by sucking carbon dioxide out of the air rather than cutting the use of oil and natural gas. “The one thing that unites us all as Americans is that we do want a cleaner, safer and healthier environment,” McCarthy told reporters Wednesday morning.

Yet a fleet of right-wing think tanks, which for decades have enjoyed considerable sway over Republican environmental policy and have made a name for themselves railing against the scientific consensus that human activity is warming the planet, aren’t yet willing to recognize the reality of human-caused climate change yet.

“The sponsors of these bills seem to be conceding the argument about whether global warming is the sort of problem or crisis that needs government action,” said Myron Ebell, an executive at one of those conservative groups, the Competitive Enterprise Institute, who sees alarm among environmentalists about global warming as a pretext for expanding government. He led Trump’s transition team for the Environmental Protection Agency. The scuffle shows how the GOP may struggle to bring nuance to its stance on climate change after years of outright denying the science.