The bipartisan House Climate Solutions Caucus lost nearly half of its Republican members in Tuesday’s elections, including co-founder Rep. Carlos Curbelo of Florida, posing a setback in efforts to break the GOP firewall on environmental issues.

Still, the group behind the initial formation and growth of the caucus says the loss, which came both through retirements and defeats at the polls, does not signal its end.

The caucus, which requires an equal number of Republicans and Democrats, was co-founded by Curbelo and Rep. Ted Deutch in 2016 to find bipartisan solutions to climate change in Congress. The caucus started with just 12 members, split evenly between both parties, at the beginning of the 115th Congress and has grown to 90 members.

“The caucus will go on. … We are confident that there are other Republicans who will step up,” said Steve Valk, a spokesman for Citizens Climate Lobby, a grassroots organization that laid the initial groundwork for the caucus and has continued efforts to coax more lawmakers to join.

Curbelo lost his re-election bid to Democrat Debbie Mucarsel-Powell in a district that covers the Florida Keys and parts of Miami and is prone to damage from sea level rise and coastal flooding made worse by climate change. Democrats, who have now picked up enough seats to gain House majority leadership, have planned to make climate change a priority in the committees that have jurisdiction over the issue.

“The fact that the Democrats are in control of the House now opens up a better possibility of moving legislation through committee and possibly on the floor,” Valk said. “But just because the Democrats are in control, doesn’t mean we can abandon the bipartisan approach.”

It is not clear who would replace Curbelo as the caucus’ Republican leader. Contenders could include Pennsylvania Rep. Brian Fitzpatrick, who narrowly won his re-election bid, and Florida Rep. Francis Rooney, who were the only co-sponsors of a carbon tax bill introduced by Curbelo in August. Neither immediately responded to a request for comment.

The caucus will reset when the new Congress takes office in January. And while the group will still require an equal number of members from each major party, Valk said, the Democrats who had been members in the 115th Congress will not be barred from rejoining alone. New Democratic members will be delayed until an equal number of Republicans have come on board, he said.

While all the GOP members of the caucus acknowledged the scientific consensus on climate change, most had not always voted for action to slow that change. Some green groups view their defeat as a win for climate action rather than a loss. Representatives the League of Conservation Voters, Environment America and Sierra Club have accused some of the Republicans of joining the caucus in the run-up to the election to boost their chances of winning in competitive districts.

“Our hope is that the Climate Solutions Caucus will be replaced with the Climate Action Caucus or Climate Honesty Caucus,” said Michael Brune, executive director of Sierra Club, which endorsed Mucarsel-Powell against Curbelo. “We need to see stronger action, not just a few good speeches made once a year.”

Despite boasting of 45 Republicans by the end of this session, the Climate Solutions Caucus has been unable to break the GOP bottleneck on climate change issues and pass any such legislation.

“Climate change will continue to be an issue, but it will require a Democratic leadership,” said Joe Bonfiglio, president of the Environmental Defense Fund’s political arm, EDF Action. It supported three GOP members of the caucus: Curbelo, Fitzpatrick and New York Rep. Elise Stefanik, who won re-election.

Bonfiglio acknowledged that simply joining the caucus wasn’t enough if not marked by action, but he said adding climate change to their campaigns is not what caused the candidates to lose.

Valk echoed similar views on the losing caucus Republicans.

“They lost because they were in competitive districts where the Democrats were highly motivated,” he said, adding that his climate message might have in fact helped Fitzpatrick win in a district that was a tossup.

Like it has done before, Valk said, Citizens Climate Lobby will deploy volunteers and constituents to use what he described as a nonjudgmental, nonpartisan approach to convince their GOP lawmakers to join the caucus.

With more Democrats now in the House than Republicans, environmental groups see a chance for climate action for the first time in eight years, although any legislation the House passes would have to get enough support in the GOP-controlled Senate and President Donald Trump’s signature.

“A lot of the people that we are electing are really savvy environmental leaders,” Wendy Wendlandt, senior vice president and political director at Environment America, told reporters Wednesday, adding that some of the defeated Republicans had been “greenwashing” their campaigns to deceive voters into thinking they cared about climate action. “We are confident that the House will be able to stand up and fight against environmental rollbacks.”

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