An incredibly important bill on climate change is being debated on the floor of the House today. The American Clean Energy and Security Act, whose lead sponsors are Rep. Henry Waxman (D-CA) and Edward Markey (D-MA) will cut carbon emissions by 17 percent below 1990 levels, promote investments in renewable energy sources, and implement the long-discussed “cap and trade” system for regulating greenhouse gas emissions. The bill is not perfect—particularly in its acquiecence to the desires of coal and corn-state legislators—and many environmentalists in Congress are hoping for stronger green protections in conference and in the Senate. (MOTHER JONES has a good roundup of “The Battle over Waxman-Markey” here.)

Just before 1pm, Speaker Nancy Pelosi brought the bill to the House floor for exactly three hours of debate—and while much of the Democratic caucus favors the bill, the vote this afternoon should be a squeaker.* (Kate Sheppard at Grist is also doing heroic reporting from the floor.)

Democratic supporters have come out swinging, calling the bill a domestic job-creating machine that will protect the environment and better position the US for both the 21st century economy and the tough climate change negotiations in Copenhagen this December. Opponents say the bill will kill the US manufacturing base and disadvantage businesses as well as rural America in general. “This bill is going to kill jobs across the country,” said Rep. Robert Latta (D-OH) on the floor this afternoon. “We can’t put the American farm behind the proverbial eight-ball.”

President Obama laid a lot of political capital on the table this week when he directly came out in support of ACES: “I believe that this legislation is extraordinarily important for our country,” he said. “These incentives will finally make clean energy the profitable kind of energy. And that will lead to the development of new technologies that lead to new industries that could create millions of new jobs in America -- jobs that can't be shipped overseas.”

The White House also sent Van Jones, green jobs “czar” and special adviser at the Council on Environmental Quality, out to the people, with this online video discussing the importance of weatherization and the development of green jobs and green industries for minorities:

Despite the potential for environmentalism to help communities of color, one of the strongest and perhaps most unexpected opponents of the bill is Artur Davis (D-AL). “This is the wrong time for cap-and-trade,” he said Friday—siding against the president whom he supported tirelessly during the 2008 campaign.

Davis, of course, may be thinking about his own campaign in Alabama, where he is running for Governor in 2010. He's tacked right on energy in order to curry favor with Independents and conservative Democrats in the south. But when it comes to the proven benefits that accrue to black folks who go green, Davis may find himself on the wrong side of the debate.

—DAYO OLOPADE

UPDATE: The House passed the bill late on Friday by a seven-vote margin, 219-212. Fourty-four Democrats voted no, and 8 Republicans crossed party lines to vote aye. The debate went on for about six hours, and produced some memorable bickering on the House floor.

Phaedra Ellis-Lamkins, a contributor to THE ROOT and head of Green For All, which promotes environmentalism in communities of color, cheered the vote, and believes "this legislation will not only position America at the forefront of the clean-energy economy but will also create jobs and opportunities for communities that are too often at the margins - and the smokestack end - of our current economy.”

Now, Obama's task may be even tougher: Cleaning up the environmental damage done just getting the House to agree on a bill, and twisting arms in the notoriously finicky Senate to keep the climate change bandwagon moving along.

Covers the White House and Washington for The Root. Follow her on Twitter.