Former Utah Gov. Jon Huntsman formally kicks off his presidential campaign Tuesday, with New York's Statue of Liberty as a backdrop. He's hoping some tired and poor Republicans are yearning for a different kind of candidate. Huntsman holds moderate views on immigration and same-sex civil unions, and he wasn't afraid to serve in the Obama administration, as U.S. ambassador to China.
As governor, Huntsman was also a leader in a regional effort to control greenhouse gases, by capping carbon emissions and trading pollution permits.
"Until we put a value on carbon, we're never going to be able to get serious about dealing with climate change," Huntsman said during a 2008 gubernatorial debate.
Since then, the political climate has changed.
"Our economy's in a different place," Huntsman told Time magazine last month. "The bottom fell out of the economy, and until it comes back, this isn't the moment" to pursue cap and trade.
Huntsman's GOP rival Mitt Romney, the former Massachusetts governor, has also backed away from cap and trade, after supporting the idea years ago.
"A lot of people have talked about cap and trade," Romney said during a town hall meeting in New Hampshire this month. "We cannot, as America, enter into agreements that cause our energy to become more expensive if we let the big emitters of the future like China and Brazil off the hook."
Another Republican White House contender, Tim Pawlenty, has backpedaled furiously on climate change, an idea he supported when he was governor of Minnesota.
"I was wrong," Pawlenty said during a GOP debate on Fox News. "It was a mistake. And I'm sorry. It was ham-fisted and it's going to be harmful to the economy."
Republican leaders' interest in global warming has cooled considerably since 2008, when John McCain was the party's standard-bearer.
"The facts of global warming demand our urgent attention," McCain said at the time. "Good stewardship, prudence and simple common sense demand that we act to meet the challenge and act quickly."
McCain's support for cap and trade was not universal in the GOP, even then. But it wasn't a huge stretch, either. After all, the idea of controlling emissions with a market-based trading system has a Republican pedigree. The first President Bush used cap and trade to combat acid rain.
In 2008, the biggest difference between McCain's plan to fight global warming and the Democrats' plan was how much each side wanted to rein in greenhouse gases: 65 percent or 80 percent. To environmentalists, that now feels like the good old days.
"Everyone agreed the sun rose in the east and set in the west," said Navin Nayak, senior vice president of the League of Conservation Voters. "Suddenly we emerge four years later, with a field of Republicans that are trying to tell us that the sun rises in the west, and we're not sure if it sets."
Some Republican White House hopefuls — notably Rep. Michele Bachman of Minnesota — question the scientific consensus that greenhouse gases are likely a leading cause of climate change.
"Carbon dioxide is natural. It occurs in earth," Bachman said during a 2009 floor speech, as the House was considering cap and trade legislation. "Carbon dioxide is not a harmful gas. It is a harmless gas."
Environmentalists give Huntsman and Romney some credit for at least acknowledging the science behind climate change. But they say simply admitting there's a problem is not enough.
"It would be like a presidential candidate saying, 'Yes, the debt is a serious crisis. But I'm not going to introduce any plan to deal with it,'" Nayak says.
Republican candidates aren't the only ones who have changed their tune in recent years. The Pew Research Center points to a sharp decline in the number of Americans who even believe that global warming is happening, let alone that it's a serious problem.
In 2006, 77 percent of Americans agreed there is "solid evidence" of global warming. By this year, that number had fallen to 58 percent. And just over a third believe that man-made carbon emissions are to blame.
"Most of that decline has occurred among Republicans and Independents," said Andrew Kohut, president of the research center. "The partisan gap is huge."
Of course, these are the primary voters that Republican candidates need to appeal to. And they've been encouraged in their skepticism of climate change by fossil fuel interests, which have bankrolled an aggressive campaign against cap and trade.
Even among Democrats, fighting global warming is not a high priority. So it's little wonder, in tough economic times, that GOP hopefuls have taken the public's temperature, and given this issue a pass.