The Hill reports that Crossroads GPS is is hitting Rep. Nick Rahall (D-WV) on coal.
The group, which is the nonprofit arm of GOP strategist Karl Rove's American Crossroads, claims Rahall "endorsed" Obama's climate agenda by backing a carbon tax.
Rahall, who is facing a tough reelection, came out in fierce opposition to the administration's proposed carbon emissions standards. The rules would mandate that the nation's fleet of existing power plants cut carbon dioxide 30 percent by 2030 from 2005 levels.
After the Environmental Protection Agency proposed the rules in June, Rahall proposed legislation to block the new standards, and has said he does not support a carbon tax.