The emerging "tri-partisan" bill on climate and energy faces a tough legislative calendar but it remains the most viable option on the table for the United States to meet its Copenhagen commitments and achieve low-carbon economic growth.

A Senate trio of a Democrat (John Kerry), a Republican (Lindsay Graham), and an Independent (Joe Lieberman) is crafting a bill aimed to appeal to a bipartisan minimum of 60 senators, an increasingly difficult task as the November mid-term elections near. But, as of today, none of the alternatives-EPA regulation, an "energy only" bill without a cap on emissions, or postponing action to a future Congress, among others-would deliver the U.S. commitment to reduce its emissions 17 percent below 2005 levels by 2020. Meanwhile, the United States remains dependent on imported oil, while China and other nations gain a competitive edge in clean energy technologies. Stakeholders on both sides of the Atlantic still need to convince wavering senators that the trio's bill has the best chance to cap U.S. emissions while strengthening the U.S. economy and increasing energy independence.