Inevitable: Lindsey Graham signs on to cap-and-trade

Graham’s support is a major win for climate supporters, who are seeking Republican support for climate legislation. A climate bill passed the House in last June, but prospects for the legislation have dimmed amid the contentious health care debate.

The Democratic Caucus is split over the climate bill, with Rust Belt senators fearing that the legislation could hurt industry and consumers in their region. The divide among Democrats means supporters will most likely need Republican votes to overcome a Senate filibuster.