For years, congressional Republicans have voiced doubts over the science behind climate change in tones ranging from merely skeptical to certain that it is not happening.
Yet no Republican leader on Capitol Hill — and few if any party back-benchers — challenged the existence of climate change when criticizing the proposed Environmental Protection Agency restrictions.
Instead, Republicans focused on other popular GOP talking points, saying that forcing power plants to significantly reduce carbon dioxide emissions would lead to higher energy prices for consumers, compromise the nation's electrical grid, hurt the domestic coal industry and cost American jobs.
To be sure, that doesn't mean Republican lawmakers now believe in climate change. It may instead simply indicate that they don't think that it's the most effective argument against the EPA's regulations at the time they are announced.
Sen. Ted Cruz, R-Texas, who previously has questioned whether global warming is real, said the proposed new EPA rules "will cripple the coal industry and deprive Americans from jobs."
"Once again, President Obama is more concerned with the desires of billionaire campaign contributors and placating extremist special interests than helping American workers and families escape the failed Obama economy," he said.
But the Texan didn't repeat comments he made in February that "data are not supporting what the [climate change] advocates are arguing."
House Speaker John Boehner, R-Ohio, called the administration's proposal "nuts."
"There’s really no more succinct way to describe it," he said. "Here he is proposing rules to ship jobs overseas for years to come."
The speaker also called the initiative a "new national energy tax" because he says it would financial burden energy companies, who would pass along their costs to consumers.
But he didn't elaborate on comments he made after the 2012 elections that he isn't sure what is causing global warming.
"I don’t think there’s any doubt that we’ve had climate change over the last 100 years," Boehner told USA Today in late 2012. "What has initiated it, though, has sparked a debate that’s gone on now for the last 10 years."
Sen. Marco Rubio of Florida, among the most high-profile Republicans climate change skeptics, didn't put out an official statement on the EPA's plan. But he told an Orlando radio station Monday that it's unfair for the U.S. to impose strict carbon dioxide restrictions on its power plants when developing economies like China and India are bigger air polluters.
"This notion that, somehow, if we destroy our economy by raising utility prices for Americans, [developing countries are] going to follow our example, is silly," the senator told told WFLA 102.5 FM. "Americans are going to pay a terrible price for these sorts of unilateral executive actions the president is taking on energy."
Rubio, a possible 2016 presidential contender, didn't question the existence of climate change during the radio interview. But last month he told ABC news he "do[es] not believe that human activity is causing these dramatic changes to our climate the way these scientists are portraying it."
"I do not believe that the laws that [the Obama administration] propose we pass will do anything about it, except it will destroy our economy," he added.
Sen. James Inhofe of Oklahoma, the top Republican on the Environment and Public Works Committee and a longtime climate change skeptic, disputed Democratic claims that greenhouse gases directly lead to respiratory and other health problems.
"This [EPA] rule is all about pushing a green agenda that has been dreamed up by the environmentalist community for decades," he said.
But Inhofe stopped short of outright denying that carbon emissions from power plants contribute to global warming, saying the U.S. "must strike a more reasonable balance of our energy resources."
"The [EPA] rule sets ambitious targets for CO2 reductions that will require the U.S. to rapidly decrease use of our cheap domestic energy resources, shut down perfectly good power plants and rely more on prohibitively expensive renewable energy, Inhofe said.
The Cincinnati Enquirer reported in March that Senate Minority Leader Mitch McConnell told its editor board he doesn't "buy the climate is changing."
But the Kentucky Republican avoided the subject Monday, instead characterizing the EPA initiative as a "dagger" thrust "in the heart of the American middle class and to representative Democracy itself."
McConnell, a vocal advocate for the coal industry, one of his state's largest employers, also accused the Obama administration of drafting the plan without consulting Congress.
"The fact that the president plans to do all this through an end-run around Congress only highlights his contempt for the wishes of the public and a system of government that was devised precisely to restrain an action like today's," he said.
Kentucky's other GOP senator, Rand Paul, a possible 2016 White House candidate, has mocked climate change advocated in the past. But his two-sentence statement on the EPA rules instead focused on the plan's economic impact.
"This latest assault on our economy by President Obama will destroy jobs here in Kentucky and across the country, and will hurt middle class families by hiking their utility bills and straining their budgets,” Paul said.
"The excessive rule is an illegal use of executive power, and I will force a vote to repeal it."
This article was originally posted at 4:43 pm has since has been updated.