IF REP. MARK CUSACK’S effort to weaken Massachusetts’s ambitious 2030 climate commitments was the first shot across the bow in the contentious energy affordability debate, the nation’s largest environmental organization is making an unprecedented move to try to blunt his influence.

The gamble from Cusack, a Braintree Democrat who chairs the House Committee on Telecommunications, Utilities, and Energy, prompted a backlash in November that knocked legislative leaders on their heels. Protesters filled the State House with signs reading, “Stop Rep. Cusack’s ‘Big Beautiful Bill,’” a reference to President Trump’s landmark law enacted last summer that featured sweeping cuts in federal support for health care and nutrition programs and clean energy initiatives.

That blowback hasn’t left Beacon Hill.

The Massachusetts chapter of the Sierra Club is set to call on House Speaker Ron Mariano to remove Cusack as chair of the powerful energy committee on Tuesday, citing his legislative efforts to use Gov. Maura Healey’s energy affordability legislation as a vehicle to pull back on the state’s clean energy targets and energy efficiency program.

Cusack also hauled in about $2,400 in campaign contributions from energy interests right around the time his plan became public and cleared his committee.

Leaders of Sierra Club’s Massachusetts chapter, which boasts 20,000 members, said those actions are enough to call for Cusack to step aside, the chapter’s first such move in its 56-year history.

“At a time of increasingly severe temperature extremes, ballooning energy demands, and utility bill spikes, Massachusetts needs someone to lead the Telecommunications, Utilities, and Energy committee who understands the essential role of clean energy and efficiency in saving ratepayers money each month — not someone who answers to the beck and call of fossil fuel interests scrambling to hold onto massive profits at our expense,” said Amelia Koch, vice chair of the Sierra Club Massachusetts Executive Committee, which unanimously voted for Cusack’s demotion.

Evan MacKay, a member of the Massachusetts Sierra Club’s executive committee who recently launched a campaign to unseat a state lawmaker representing Cambridge, is expected to be one of the speakers at a Tuesday press conference to push for Cusack’s ouster, according to Vick Mohanka, director of the state’s Sierra Club chapter.

Cusack didn’t respond to a request for comment, but Mariano harshly criticized the Sierra Club’s call for him to replace the energy committee chair.

“With this foolish request, the Massachusetts Sierra Club is demonstrating a complete lack of understanding of the legislative process, and is simply overreacting to old news stories about an outdated committee redraft of the House’s energy affordability legislation,” Mariano said in a statement. “Just last week, [Ways and Means] Chairman Michlewitz and Chairman Cusack hosted several member meetings regarding this bill and are now working to incorporate the feedback that they received. For months now, the House has been clear that this legislation will not alter the state’s climate goals or retreat from our commitment to clean energy. Instead, our sole focus is on bringing down energy costs for residents, a goal that everyone should be capable of supporting.”

Such a bold move from a progressive but mainstream environmental organization kicks the already-high tension around energy issues in Massachusetts up a notch and offers somewhat of a finer point on the political fallout from Cusack’s proposal last year. It comes as House members are debating how best to tackle soaring electric and heating costs, a pocketbook issue only bound to intensify as Healey seeks reelection, even with legislative leaders taking Cusack’s attempts to walk back the larger emission reduction commitments off the table for now.

Still, Sierra Club’s decision to call for Cusack’s ouster comes with its own consequences, too — and has left some allies scratching their heads over the tactic.

Two advocates at different environmental groups in Massachusetts, granted anonymity to express concern with the Sierra Club plan, told CommonWealth Beacon they are worried about the potential negative impact during a tenuous time in the legislative negotiations and questioned what such a move would achieve.

While there’s little chance that Mariano would actually remove Cusack from his perch as chair of the committee, it could become harder for the Sierra Club and, by extension, other like-minded environmental groups to get meetings with lawmakers and be given access to influence the ongoing internal deliberations.

Plus, these advocates argued that environmental groups are making inroads in shaping the measure to more closely align with their policy objectives after House leadership halted Cusack’s original version from quickly advancing. While there remains an appetite among lawmakers to cut or cap the Mass Save energy efficiency program, the bill could be moving back toward the center as it appears unlikely that language to dial back the climate goals will remain in the legislation as it makes its way to the full chamber for a floor vote. Sierra Club’s move, they worry, could undermine the progress the groups feel they are making.

Not everyone agrees that Sierra Club’s move has drawbacks. Jonathan Cohn, policy director at the advocacy group Progressive Mass, said it’s clear from Cusack’s November version of the energy affordability bill that he isn’t taking his cues from groups like Sierra Club anyway.

“From the universe of not wanting to deny yourself access, if you never had access to begin with, there’s at least not as much in the way of real loss,” Cohn said. “And evaluating how back in November environmental groups across the state were able to rally members and make enough representatives scared to vote yes on his bill, it showed that power lies in that ability to have an organized and mobilized grassroots base. Trying to defeat that bill on the basis of only talking to the highest people in the building was not going to be a viable strategy.”

House lawmakers met for six hours behind closed doors last week to find consensus on a high-profile energy affordability package. Healey herself is looking to show voters she’s willing to take on the issue as she heads into an election year.

“I filed energy affordability legislation to get us more power, get costs down, and save you $13 billion,” she said in her annual State of the Commonwealth speech last week, where she outlined a plan to cut utility rates in February and March. “Our strategy on supply is ‘all of the above’ — wind, solar, hydro, gas, nuclear – whatever it takes to power our homes and businesses and cut your costs.”

But Sierra Club’s willingness to play attack dog represents the latest wrinkle in the bill’s topsy turvy process thus far and, despite uncertainty over how it will land in the State House, is a risk the group is taking on.

Some advocates, though, are trying to put distance between their groups and Sierra Club’s move to call on Cusack to be removed from his post as chair.

“None of us like the … bill, but the action has moved to Ways and Means,” one advocate said, underscoring the point that Cusack has a less singularly important but still influential role in crafting the bill than he did last year. “We’re encouraging interested people to keep engaging with all House members.”