"I think we should make sure they are exempt since they are not the big greenhouse-gas producers," said Baucus.

But Sen. Barbara BoxerBarbara BoxerAnother day, another dollar for retirement advice rip-offs Carly Fiorina 'certainly looking at' Virginia Senate run Top Obama adviser signs with Hollywood talent agency: report MORE (D-Calif.), chairwoman of the Senate Committee on Environment and Public Works, said the amendment would lead to greater pollution and undermine the EPA. 

The vote was the first of three votes being held Wednesday afternoon that would limit the EPA's jurisdiction over greenhouse-gas emissions. Four other votes unrelated votes will follow.