Republican attempts to put the brakes on environmental regulations are translating into big bucks for their opponents.

Environmental organizations say they have seen record growth in their members and donations this year, partly because of the galvanizing effect of being under attack.

“When you can fight something, I think that definitely makes people more energized,” Rebecca Connors, Friends of the Earth’s online director, said in an interview.

The group’s membership has increased 14 percent this year, according to Connors, and it has raised twice as much money since June as it did in the first half of the year.

House Republicans passed a measure last week that would delay regulations on cement manufacturing plants that environmentalists say are a major source of pollution. The activists accused Republicans of trying to undermine the Clean Air Act and the Environmental Protection Agency tasked with enforcing it.

Republicans aren’t the only ones opposing environmental rules. Conservation groups have also criticized the Obama administration for backing a pipeline that would import oil extracted from Canadian oil sands, an issue that has prompted widespread protests.

Being the underdog in those fights has benefited the League of Conservation Voters, which publishes an annual environmental scorecard rating lawmakers on their votes.

“We’re definitely seeing a dollar boost,” Vice President of Communications Mike Palamuso said. “Our members are very clearly responding to the unprecedented number of attacks from House Republicans.”

The league’s email list, which it uses to solicit donations and drive grass-roots advocacy, grew by 33 percent this year. A recent fundraising email to that list said: “Majority Leader Eric Cantor (R-Va.) and the rest of the Republican Leadership have put a target on the EPA and bedrock public health protection. … Enough is enough. Help L.C.V. hold lawmakers responsible for their votes.”

The best chance for the House-approved cement measure and a similar measure for industrial boilers to get through the Senate appears to be if it is attached to a vital appropriations bill. Sen. Susan Collins (R-Maine) has said she will consider doing that for the boiler legislation. Sen. Barbara Boxer (Calif.) and other Democrats have promised to block any such attempt.

Other environmental groups, including Sierra Club and the Natural Resources Defense Council, have also highlighted Republican actions as a way of prompting action and expanding membership. Both groups declined to discuss their fundraising efforts for this story.

“Organizations that prove to be nimble and respond to political attacks can use that to further their mission,” said Karin Cox, co-founder of Hartsook Cos., which provides fundraising assistance to nonprofits.

Online fundraising has made it a lot easier to be nimble, Cox pointed out. Friends of the Earth and the League of Conservation Voters said much of their growth came from social media and online campaigns.

“It’s easier to give. I see the news and I can make a gift on my cellphone while watching it, while the issue is on my mind and my heart,” she said.

For environmental groups, the focus on fundraising has come at a time when their policy agenda has been sidelined by a political focus on jobs and deficit reduction. The current political climate is a far cry from the environment-friendly mood prior to the midterm elections, when advocacy groups and the Obama administration helped pass a comprehensive climate change bill through the House.

When the bill failed in the Senate, Palamuso said environmental activists started giving more, not less, to his organization.

“There was a lot of speculation that folks were going to be down heading into the election, but we raised and spent more money on that election than ever before,” he said.

The league’s political arm raised more than $1 million for 2010 and has already started fundraising for the next election. Meanwhile, the group’s nonpolitical side is using the money raised to pay for online campaigns and to improve its website.

“Threat will always drive fundraising,” Palamuso added.

But it’s unclear how strong of threat there really is. Democrats still control the Senate and White House, making the anti-regulation bills favored by the House difficult to enact.

“Just as House Republicans are playing to their base, environmental groups are playing to theirs,” said Paul Bledsoe, a senior adviser on energy issues at the Bipartisan Policy Center.

The focus on Republican actions helps keep environmental groups relevant at a time when Congress is focused on other issues. The groups are “grappling to find issues that assert their near-term political relevance,” Bledsoe said.

While the groups haven’t made much progress on Capitol Hill, Connors of Friends of the Earth said there have been victories elsewhere. Her group recently sued the State Department to halt the Canadian oil sands pipeline. It also released a series of emails, obtained through a Freedom of Information Act request, that activists say show the Obama administration has favored the pipeline despite concerns about its environmental impact.

“People that we thought would be allies definitely have not been,” Connors said of the administration. “What has been a boost to our efforts is that people have been seeing us make tangible headway on what they see as a big problem.”

Correction: Oct. 13, 2011

This article originally misstated which measure Sen. Susan Collins (R-Maine) backs. She supports legislation to delay environmental regulations for industrial boilers.