Republican presidential candidates Jon Huntsman and Mitt Romney greet to each other prior to marching in a Fourth of July parade in Amherst, New Hampshire. (Darren McCollester/GETTY IMAGES)

Huntsman isn’t alone among 2012 contenders or other prominent Republicans in affirming man’s involvement in climate change. Former Massachusetts governor Mitt Romney and New Jersey Gov. Chris Christie (R), and former House Speaker Newt Gingrich(Ga.) are right there with him.

“They’re trying to appeal to moderates without angering the base. But it leaves you really exposed to the followup question — ‘What would you do?’” said Mike McKenna, a Republican strategist who works on energy issues. “I’m curious to see what Romney and Huntsman will do when that question comes up.”

While Gallup finds that 52 percent of Americans think pollution is responsible for global warming, that’s a 20-point drop from the late 1990s. Republicans are largely responsible for that drop — while 71 percent of Democrats think human activity is responsible for global warming, only 36 percent of Republicans agree.

In another sign of how views have shifted in the past two decades, Huntsman was attacked by some conservatives for hiring to his 2012 campaign Mark McIntosh, an environmental lawyer from the George W. Bush administration. A columnist at the right-wing Washington Examiner compared the move to hiring an adviser to Al Gore.

But when it comes to policy, there’s little daylight between more moderate Republicans and climate change skeptics.

As governor of Utah, Huntsman backed a regional cap-and-trade program. He opposes it now.

Last week, in response to Texas governor and 2012 candidate Rick Perry’s doubts about climate change, Huntsman tweeted: "I believe in evolution and trust scientists on global warming. Call me crazy.”

The tweet went viral, and Huntsman followed up Sunday on ABC’s “This Week,” saying “I think there’s a serious problem. The minute that the Republican Party becomes . . . the anti-science party, we have a huge problem.” Yet when asked what he wants to do about global warming, Huntsman says little.

“Cap-and-trade ideas aren’t working; it hasn’t worked, and our economy’s in a different place than five years ago,” he told Time in May. “Much of this discussion happened before the bottom fell out of the economy, and until it comes back, this isn’t the moment.” In a July Politico interview, he elaborated: “I mean, the debate doesn’t stop. It’s simply that anything that would carry with it any kind of approach on the cost side is not in play today.”

Meanwhile, New Jersey Gov. Chris Christie (R), who has toyed with a 2012 presidential bid, declared last Friday that “climate change is real,” while vetoing a bill that would have forced his state to stay in a regional program to curb greenhouse gases. Christie plans to pull out of the program by the end of the year.

Romney has long argued that climate change is at least in part man-made. “I believe the world is getting warmer, and I believe that humans have contributed to that,” the 2012 candidate said in June. “It’s important for us to reduce our emissions and pollutants and greenhouse gases that may be significant contributors.”

But in July, Romney said, “The EPA is getting into carbon footprints and I think we may have made a mistake ... I don’t think carbon is a pollutant in the sense of harming our bodies.” (When Romney was governor of Massachusetts, he initially backed a regional greenhouse gas reduction initiative before withdrawing support in 2005, saying the program would hurt the economy.)

Meanwhile, Gingrich has long argued that global warming is a problem, saying in 2007 that “there is a consensus that for the last 100 years the planet's gotten somewhat warmer. The second consensus is that humans have contributed to that.” But he opposes regulation.

All these politicians say they support a solution based on the free market and alternative energy. None of them have been very specific.

Looking at polling, it’s easy to see why Republicans are treading a fine line. While a majority of Americans support environmental regulation, in January of this year only 32 percent of respondents in a Post-ABC News poll said global warming should be a high priority for Obama and Congress. The same number told Gallup this March that they see it as a serious threaty.

“I would be surprised if President Obama talks about the science of climate change in the 2012 campaign,” said George David Banks, a senior staff member for Republicans on the Senate Committee on Environment and Public Works.

Just believing in global warming is risky territory for Republicans. Backing environmental regulation would be a dangerous leap in the primary with little hope of payoff in the general election.

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