In early October, Hillary Clinton and Barack Obama unveiled their campaign platforms on energy and the environment. John Edwards hasn’t made an event out of his, but he has one, and so do the other Democratic candidates. All of them support some kind of legislation to curb climate-warming greenhouse gas emissions, but they might be doing so at their own peril, a recent headline suggests.

Coverage of the candidates’ green credentials has picked up in the last month. Most of the stories, quite responsibly, have tried to pick out the finer differences among their various platforms (there are some). Given the widespread and novel agreement among Democratic (and some Republican) candidates on climate issues, however, it’s no surprise that support for initiatives, like cutting carbon or developing renewable fuels, is generally reported as playing to a candidate’s advantage. Many papers have noted Bill Richardson’s one-upmanship: calling for a 90 percent cut in greenhouse gas emissions by 2050, while other Dems stick to the 80 percent that the scientific community counsels.

Indeed, energy and the environment have been a source of strength for the Democrats in particular. Three weeks ago, The New York Times ran an article that described how global warming is beginning to “divide G.O.P. contenders.” Now, compare that to this headline in yesterday’s Washington Post: “Climate is a Risky Issue for Democrats.” The concern that the public may react unfavorably to a strong pro-environment platform in the general election is a fairly novel idea for news pages, and Post writer Juliet Eilperin makes the case that it’s legitimate.

It’s hard to imagine, perhaps, that endorsing emissions reductions and renewable fuels could hurt a candidate in 2008. Everywhere-from politics, to business, to academics, to consumer affairs-people say they want to reduce their carbon footprint. And for at least a year, environmentalists have voiced an near certainty that whoever lands in the Oval Office next will surely support federal action on climate issues. But all the go-green rhetoric belies what are still significant disagreements among the general public on this subject.

“The issue has turned into a Democratic litmus test,” Eilperin writes. (In order to pass the test, many candidates have paid to offset their campaigns’ sizeable emissions.) “Democrats’ boldness, however, could carry a political price.”

Not everybody has the money to pay for travel or their home’s energy use, let alone to offset them by shelling out more cash to plant trees or capture methane. Primary elections and caucuses aren’t really the concern here, but as next November approaches, voters will inevitably begin to realize that global warming is essentially an energy issue, and that an energy issue is essentially a pocketbook issue. Then, even among voters that are environmentally sympathetic, the question becomes, “What can I afford?”

As Eilperin wisely points out in her article, reducing current greenhouse gas emissions 80 percent by 2050 “is a plan that will require a wholesale transformation of the nation’s economy and society.”

This is certainly true, but the more important question is, what kind of transformation will this be? There is a lot of disagreement on this point, to put it very mildly. Yet even those that predict (as all Democratic candidates do) that green industries will be a boon for economies worldwide, admit that such gains are a long-term projection. In the short term, there will be possibly significant costs, because all change is subject to overhead expenses that pay for designing and building new technologies and systems. Matthew Wald has a useful, hard-numbers breakdown of how imposing different costs per ton of carbon might affect renewable fuels development (but not people’s wallets) in a New York Times special section on green business today.

In the Post, Eilperin gets a good quote from John Edwards, seen as a leader in the environmental arena, on anti-warming legislation: “I’d be the first to tell you: this is not necessarily the greatest political calculation.” Of course, he’s not really the first person to tell us this. Most Republicans (with the exception of John McCain and now Mike Huckabee and Sam Brownback) have been praying that it’s true all along.

Curtis Brainard is the editor of The Observatory, CJR's online critique of science and environment reporting. Follow him on Twitter @cbrainard.