House Energy and Commerce Committee Chairman Henry Waxman (D-CA) and Rep. Ed Markey (D-MA) are rolling out their proposal to cut carbon emissions today, and early leaks of the plan suggest that the duo is prepared to ensure that the Obama administration is not the most liberal player in the climate change debate.

Waxman and Markey's bill will set targets of a 20% reduction in emissions by 2020, compared with Obama's proposed 15% cut, and an 83% reduction by 2050, a more ambitious goal than Obama's planned 80% trimming. This is more than just a numbers game: By moving the goalposts further left than the White House, the two House Democrats set the stage for a meaningful compromise on climate change ... but can it happen this year?

It's a decidedly open question, particularly as health care reform moves on the budget-reconciliation fast track and the mainstream media (falsely) depicts Congress as facing an either-or choice between legislating on health and legislating on emissions.

Senate Republicans are already gearing up to ensure that climate change stalls on their end of the Capitol this year. Two GOP amendments to the Senate budget, slated for debate today, would prohibit Democrats from using reconciliation to cap carbon emissions and bar any climate change bill that resulted in an electricity or gas price hike for consumers.

(For a closer look at some of the forces dedicating to keeping the skies clogged with carbon emissions, check out TPM's new slideshow of notable climate change deniers.)

If Waxman and Markey's bill doesn't succeed in pushing climate change over the finish line this year, however, Congress may find itself cut out of the debate entirely. The Environmental Protection Agency is laying the groundwork to give the White House regulatory authority to limit emissions under the Clean Air Act -- thus giving President Obama the option of sidestepping congressional inaction, if he decides to use that stick.

Late Update: Here's early reaction to the Waxman-Markey plan from Joe Mendelson, global warming policy director at the National Wildlife Federation:

The Waxman-Markey proposal puts Congress on course to answer the President's call for comprehensive energy legislation. The plan recognizes our dependency on fossil fuels is a triple-threat to our economy, energy security and environment. We applaud Chairman Waxman and Chairman Markey for providing the leadership to keep Congress on an ambitious timetable to achieve a clean energy future. Repowering America with clean energy solutions will create jobs, end our dependence on oil, and help avoid the worst consequences of global warming.