Senate Minority Leader Mitch McConnellAddison (Mitch) Mitchell McConnellDems confront Kelly after he calls some immigrants 'lazy' McConnell: 'Whoever gets to 60 wins' on immigration Overnight Defense: Latest on spending fight - House passes stopgap with defense money while Senate nears two-year budget deal | Pentagon planning military parade for Trump | Afghan war will cost B in 2018 MORE (R-Ky.) and his Republican colleagues likened the climate change bill now before the Senate to a tax hike.

McConnell, who opposes the bill along with other GOP senators, pointed to a federal study by the federal Environmental Protection Agency that said that the measure would raise gas prices by 53 cents. The bill seeks to place mandatory caps on greenhouse gas emissions.

"With gas prices being the number-one issue in America, they bring up a bill... that objective analysis concludes it's going to raise gas taxes 53 cents," he said. "We're happy for this debate. We're thrilled about it. I've never seen my members so excited in recent times over getting out on the floor and talking about a really, really bad proposal."

The bill is being pushed by Sens. Joe Lieberman (I-Conn.) and John Warner (R-Va.). Many Democrats, including Majority Leader Harry ReidHarry Mason ReidTo end sugar subsidies, conservatives can't launch a frontal attack House presses Senate GOP on filibuster reform A pro-science approach to Yucca Mountain appropriations MORE (Nev.), also back it.

Sen. Kit Bond (R-Mo.), appearing with McConnell, said that the $6.7 million price tag for the bill, which proposes funding for research and development of new energy sources, won't be paid by energy companies.

"It's going to be passed right through to you and me as consumers," Bond said. "Whether the bill sponsors admit that their bill is a hidden tax hike or not, we know it will hurt families and workers. We know, if it walks like a duck and quacks like a duck, it is a duck. And that is a tax hike."