Hey, look: Environmentalists are suddenly getting excited again. Remember the old renewable electricity standard? The one that would force utilities to get 15 percent of their power from sources like wind, biomass, and solar by 2021? It wasn't the greatest clean-energy policy of all time, but it was something. And it's slowly creeping back into the Senate conversation: Jeff Bingaman (D-NM) is trying to resurrect it, and he's already snagged four Republican co-sponsors—Sam Brownback, Chuck Grassley, Susan Collins, and John Ensign. So does this thing actually have a chance?

It's possible, but the odds are still extremely long. And four Republican co-sponsors won't be enough. "Realistically, this bill will need at least a half-dozen Republicans actively supporting it," says Dan Weiss of the Center for American Progress. For one, a bunch of Senate Democrats flatly oppose an RES, including Evan Bayh, Ben Nelson, Mary Landrieu, Blanche Lincoln. Second, if this bill doesn't come up until the lame duck session after the midterms, there's going to be enormous pressure on Republicans from the Senate leadership not to cooperate on anything. Which means it'll need an even bigger critical mass of support.

Are there other potential Republican co-sponsors lurking out there? The names most commonly kicked around are Olympia Snowe of Maine, Scott Brown of Massachusetts, and, as a long shot, maybe even John Thune (South Dakota has a lot of wind-power potential, and the state already has a voluntary goal of 10 percent renewable by 2015). One complication, though, is that the bill's strongest GOP advocate, Sam Brownback, is almost certainly going to get elected governor of Kansas in November, and he'll be busy with the transition during the Senate's lame-duck session. Also note that two states, Illinois and West Virginia, would seat their senators immediately after the election, so if Republicans win either of those seats, the lame-duck vote gets tougher.

So the bill's not there yet. Granted, Jeff Bingaman has a decent track record of charming Republicans and corralling votes. Against that, however, it's now looking like Democrats are going to spend their time after the midterms figuring out whether and how to extend the Bush tax cuts, which leaves a lot less time for energy issues.

Substantive question: Would the RES still be worth doing? I've written before about how Bingaman's renewable electricity standard is pretty weak—according to a Union of Concerned Scientists analysis, it wouldn't do all that much over and beyond what the 30 states with their own standards already require. But when I asked Marchant Wentworth of UCS about this, he pointed out that simply getting a federal standard in place is also important: It would open up new markets for clean energy in the Southeast, and it would give more regulatory certainty to the wind and solar industries. The historical pattern with most states is that they pass an RES, find out that it's far easier to meet than expected, and then strengthen it. Taking that initial plunge is usually the most difficult step.