Bachmann: If Huntsman falls near the Romney end of the spectrum, Rep. Michele Bachmann's, R-Minn., views align closely with Perry's. "I believe that all of these issues have to be settled on the base of real science, not manufactured science," she said this week on the campaign trail in South Carolina when asked about climate change. In a 2009 speech on the House floor, Bachmann expanded on her thoughts on carbon dioxide. "Carbon dioxide is natural. It occurs in Earth," she said. "It is not harmful. It is a part of Earth's life cycle. And yet we're being told that we have to reduce this natural substance and reduce the American standard of living to create an arbitrary reduction in something that is naturally occurring in the earth." Paul: Rep. Ron Paul, R-Texas, is also on the global-warming-is-made-up-science page. Though in 2007 and 2008 he was considering the possible role of human activity in global warming, by late 2009 he told Fox Business, "you know the greatest hoax I think has been around many many years, if not hundreds of years, has been this hoax on the environment and global warming." Gingrich: While former House Speaker Newt Gingrich had done an ad in 2008 with then-House Speaker Nancy Pelosi on addressing climate change, he is another candidate who has since changed his stance. In the ad, Pelosi notes that the two politicians don't always see eye to eye. "No," says Gingrich. "But we do agree, our country must take action to address climate change." In a radio interview this year, however, he said he regretted doing the ad. "I was trying to make a point that we shouldn't be afraid to debate the left, even on the environment, but obviously it was misconstrued, and that's one of the things I probably wouldn't do again." He also moved toward the questioning-the-science point of view in an interview last year, saying, "I don't think we're faced with a crisis of global warming. I think in fact that the scientific data is still very unclear." Santorum: Former Sen. Rick Santorum, R-Pa., outlined his thoughts on the matter in a June interview on Rush Limbaugh's radio show, putting himself squarely in the humans have nothing to do with it camp. "I believe the Earth gets warmer, and I also believe the Earth gets cooler, and I think history points out that it does that," he said. "The idea that man... is somehow responsible for climate change, I think is patently absurd." For the left, he went on to say, "It's really a beautifully concocted scheme." Cain: Businessman Herman Cain laid out his position in June on Mark Levin's radio show. "Man-made global warming is poppycock. I hope I can say that on your show," he said. In case that wasn't clear: "In other words, I don't believe in it."