Congressional Republicans have promised a robust response to President Obama's carbon-emission rules for power plants, and the Senate Wednesday lined up their first real piece of ammo.

And Democrats showed that they're going to take their Republican opponents to the mat over the reality of climate change.

After a messy markup that saw Democrats walking out, the Senate Environment and Public Works Committee cleared a bill from Sen. Shelley Moore Capito that would force the Environmental Protection Agency to scrap the power-plant rules and rewrite them under much more narrow conditions.

The bill passed with only Republican votes; Democrats, led by ranking member Barbara Boxer, walked out of a markup because the committee was voting on a separate pesticides bill that had not been through a hearing, leaving the committee without a quorum. As a result, Chairman James Inhofe was forced to suspend the markup and finish it off the floor in the afternoon, with no Democrats participating.

Capito's bill is just one of the vehicles that Senate Majority Leader Mitch McConnell has promised to use to fight the climate rules. McConnell has said that Republicans will use the Capito bill, appropriations riders, and Congressional Review Act resolutions to strike back at the climate rules.