A compromise energy bill that many viewed as the best hope for U.S. climate change legislation this year hit a roadblock over the weekend when its Republican sponsor, Sen. Lindsey Graham of South Carolina, withdrew his support in a feud with Democrats over timing for moving the legislation.

The bill was supposed to be introduced Monday with the backing of the Edison Electric Institute, which represents most U.S. electric utilities, and three of the nation's largest oil companies.

Graham has been working for several months on the bill with Sens. John Kerry, D-Mass., and Joseph Lieberman, I-Conn. It would take effect in 2013 and by 2020 would cut U.S. greenhouse gas emissions 17 percent compared to 2005 levels, and 80 percent by 2050, Kerry said last week.

On Saturday Graham announced that he would suspend his involvement in the climate bill because of what he termed the Democrats' “cynical ploy” of focusing first on immigration reform.

Late last week after the passage of a highly controversial state law in Arizona that gives police broad powers to crack down on illegal immigrants, the Democratic leadership began considering moving immigration reform ahead of climate legislation in their congressional priorities. Graham said that would make it impossible to also pass a climate change bill this year. But Time magazine speculated that he may also have pulled back support due to political pressure from opponents of climate change legislation.

For background on the U.S. climate change policy debate, read the Cover Story in InsideCounsel's April issue.