The climate debate may finally be simmering.

Al Gore is leading a last-bid effort to save the cap and trade concept as the three Senators who have been drafting a bipartisan bill move away from it.

But even as Gore’s group stepped up its efforts, other environmentalists seemed ready to compromise. Even opponents of climate regulation have found something to like about the new proposal being unveiled this week.

Senate Democrats know they need cross-party support to get a climate bill past a filibuster. Republican Lindsey Graham of South Carolina has been working with John Kerry (D-Mass.) and Joseph I. Lieberman (I-Conn.) to hatch a plan both parties could support.

As that proposal is rolled out, Graham noted in no uncertain terms that cap and trade – which would require companies to buy and trade carbon credits that limit their emissions – was not part of it.

“The cap-and-trade bills in the House and Senate are dead,” the Washington Post   reported him saying last week.

On Tuesday, Repower America, the advocacy group Gore started, launched “an all-out, bare-knuckled, three-day calling campaign” to persuade lawmakers to keep cap and trade. In an e-mail, the group told members to seek a carbon limit on “all sectors of our economy.”

“I hope that it will place a true cap on carbon emissions,” Gore wrote of the upcoming Senate plan in a New York Times editorial   last week.

But the trio of Senators are backing sector-by-sector controls on greenhouse gas emissions that target the nation’s biggest polluters and may bring moderate lawmakers from coal and oil states on board.

Their idea   is to cap emissions solely on the electric utility industry, tax the transportation sector for using fossil fuels, and eventually phase in regulation of manufacturers.

It may not be the overarching cap and trade concept as laid out in the House bill (HR 2454 ), but the proposal has pleased some environmentalist groups.

“We’re okay with a variety of approaches being employed,” Sierra Club spokesman Josh Dorner said, “as long as we have an overall target and path to reducing our emissions.”

On the other end, opponents of cap and trade say the new proposal is too rigid. An emissions cap on power plants is still too broad reaching for them.

“That’s hardly a win or a concession,” Jacob Leis, who runs Western Tradition Partnership, said. “That still affects everyone who lives in a home or turns on a light switch.”

Leis’ group has several thousand individual members who oppose taxing carbon.

“We need to step away from the notion that carbon is an evil and the best way is to raise taxes,” he said.

But the bipartisan bill does have some aspects Leis likes. Offshore drilling and nuclear power plants are among the concessions Republicans have been able to get.

Even though groups like Sierra Club oppose those ideas, Dorner said they were not deal breakers.

“If the bill will otherwise save the planet, it’s probably not something we would turn our backs on,” he said.

Ambreen Ali writes for Congress.org.

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