Progressives around the country cheered when Ned Lamont knocked out Sen. Joe Lieberman in Connecticut’s Democratic primary last month, but some enviros held their applause.

Joe Lieberman.

Photo: Paul Morigi/ WireImage

Lieberman — now running as an independent in an effort to hold onto his seat — has, by most accounts, been a standout leader on environmental protection during his 18 years in the Senate. While longtime allies like John Kerry, Hillary Clinton, and fellow Connecticut Sen. Christopher Dodd are among the many high-profile Democrats backing Lamont, some leading greens are vowing not to leave Lieberman’s side.

The League of Conservation Voters, which ranks Lieberman’s lifetime voting record at 86 percent (one of the highest scores the group has tallied for a long-running congressional career), says it plans to stand by the endorsement of the senator it issued in March. “We’ve looked very carefully at his decision to run as an independent, and unanimously agreed to maintain our endorsement,” said Tony Massaro, LCV’s senior vice president for political affairs. “Not only do we support Sen. Lieberman, we’ve named him an environmental champion — a title we give out very sparingly. His exceptional leadership should be supported no matter what party he belongs to.”

The Sierra Club has not yet announced whether it will endorse Lieberman, but the group’s spokesperson, David Willett, stressed that the senator’s party affiliation will have no impact on the decision: “We endorse people, not parties.”

Lieberman’s name is best known in environmental circles in connection with the Climate Stewardship Act he initially introduced in 2003 with Sen. John McCain (R-Ariz.), reintroduced in 2005, and plans to continue pushing this fall. The first federal bill to propose a cap-and-trade program for greenhouse gases, the act would impose a limit on emissions and allow companies to meet that limit by buying and selling the right to pollute. Lieberman has been a staunch defender of the Arctic National Wildlife Refuge and a vocal critic of President Bush’s environmental agenda. He helped draft the landmark 1990 Clean Air Act amendments, and last year cosponsored the bipartisan Vehicle and Fuel Choices for American Security Act, which would reduce U.S. oil consumption by 10 million barrels a day in the next 25 years.

In contrast, Lamont doesn’t have much of an environmental record to point to — largely because he doesn’t have much of a political one. A well-heeled technology entrepreneur, Lamont’s political experience consists of chairing the state investment advisory council and serving on a smattering of civic boards. Nevertheless, if elected, it’s expected he would vote with the majority of fellow Dems for strong environmental protections. In fact, Lamont suggests on his campaign website that he would be a stronger green champion than his opponent, and criticizes Lieberman’s support for the 2005 energy bill, “which features billions in subsidies to big oil and does little for conservation and energy efficiency.” Lamont also claims he is serious about fighting global warming “in the arenas that really matter — the courts and the federal government.”

Lieberman’s communications director, Dan Gerstein, argues that Lamont wouldn’t have nearly as much sway on environmental policy as Lieberman, who has been a longtime member of the Environment and Public Works Committee and has played a high-profile role forging bipartisan support for environmental bills. “Lieberman has been both a leader and a key consensus builder on green issues,” Gerstein said. “Without him, climate politics changes. The whole landscape of environmental policy changes. … Joe Lieberman has been at the forefront of pretty much every effort to block the administration’s rollbacks of environmental standards.”

The Fog of War

Lieberman seems to be leading in the race, but only slightly. Recent polls by the American Research Group and Rasmussen Reports show the senator with a slim two-point lead over Lamont, while a Zogby poll has Lieberman leading by 10 points. (Republican Alan Schlesinger — who is playing a largely symbolic role and doesn’t even have strong support from the party establishment — pulled only 2 percent support in the Zogby poll.)

“I am a Democrat,” Lieberman declared recently on CBS’s Face the Nation. “Look at my voting record. I voted 90 percent of the time with the majority of Democrats in the United States Senate. But when I disagree, I’m going to have the courage of my convictions to say so.”

The big point of disagreement, of course, is Lieberman’s unwavering support of the Bush administration’s war in Iraq and broader “war on terror”; it’s the reason Lamont launched his challenge, and the reason so many Democratic voters have backed Lamont.

Some enviros argue that this issue alone renders moot Lieberman’s impressive environmental track record. Says Adam Werbach, former president of the Sierra Club and prominent green activist, “Lieberman’s party should be irrelevant if you’re an environmental-issue voter. The big question is whether you believe the Iraq war is an ‘environmental’ issue. I do. For me, the Iraq war is a travesty — ecological and otherwise — that far outweighs Lieberman’s stellar environmental record.”

Dem’s the Breaks

The Lieberman/Lamont contest raises questions about how closely aligned environmentalists are — or should be — with the Democratic Party.

The same issue has cropped up during the reelection campaign of Sen. Lincoln Chafee (R-R.I.), a moderate Republican who’s widely seen as an environmental leader, and who’s in serious danger of losing to Democratic challenger Sheldon Whitehouse (if he even survives a tough challenge in the Republican primary). The Sierra Club has endorsed Chafee, and for that the group recently got spanked by liberal New York Times columnist Paul Krugman: “If the Democrats gain only five rather than six Senate seats this November, Sen. James Inhofe [R-Okla.], who says that global warming is ‘the greatest hoax ever perpetrated on the American people,’ will remain in his current position as chairman of the Senate Environment and Public Works Committee. And if that happens, the Sierra Club may well bear some of the responsibility,” Krugman wrote.

But a vote for Lieberman is a far cry from a vote for Chafee, who would prop up the anti-environment GOP leadership in Congress. Though Lieberman would be an independent, he would caucus with the Democrats, says Gerstein, his communications director, thereby helping the Democrats retake the Senate.

Lieberman’s campaign could, however, inadvertently hobble Dems’ chances in the House. Here’s why: Connecticut has three Democratic candidates who have a decent chance of unseating the state’s incumbent Republican representatives: Nancy Johnson, Christopher Shays, and Rob Simmons. As The New York Times reported this week, “Democratic officials say they expect Mr. Lieberman to campaign aggressively to win over Republican and unaffiliated voters. If he does, Democratic strategists say, he may well attract voters to the polls who are likely to support the state’s three Republicans in Congress.”

While some enviros argue that Johnson, Shays, and Simmons have been allies in important battles like the fight to protect the Arctic Refuge, their three contested seats represent one-fifth of the 15 seats Dems need to regain a majority in the House — and to put the House agenda in the hands of Nancy Pelosi (D), who’s got a respectable environmental track record, instead of Dennis Hastert (R), who doesn’t.

Sierra Club Executive Director Carl Pope, though, argues that it’s bad long-term strategy for environmentalists to align themselves with one party. “Our job is to reward conviction, applaud leadership, and promote progress made in cleaning up the air and water and in preserving our wild lands and wildlife — no matter which side of the aisle we find it on,” he wrote in his blog in response to Krugman’s broadside.

Whether the Sierra Club will endorse Lieberman — and whether that will help the senator win the fight of his life — remains to be seen.