While doing some research today, I came across this 2007 blog post from US News & World Reports discussing a Mitt Romney television appearance before he formally announced his intent to run for office:
Romney gave some vague answers regarding his views on dealing with climate change, other than to emphasize that he wanted market-oriented solutions. But Romney, a guy who is trying to portray himself as a follower of Reaganomics, never really contested the underlying science. And probably no major 2008 candidate will either, for fear of being labeled a scientifically illiterate know-nothing.
Oh, 2007. You were so quaint!