The Yale School of Forestry & Environmental Studies, one of the world's leading research institutions in the field of social behavior relating to climate change, recently released a report called "Global Warming's Six Americas" (PDF). The report was led by Dr. Anthony Lieserowitz, the head of the Yale Project on Climate Change, who explains that unlike other countries, the U.S. has six distinct populations, all of whom relate to climate change in different ways.
A couple of interesting findings. The first is that of all the "issue populations" (i.e. the percentage of the population that advocates about a particular issue — immigration, health care, education, etc.) climate change is the largest — a full 18 percent of the adult population. And additional one-third of the population is very concerned about climate change.
A full one-fifth of the population is somewhat concerned but feels underinformed. These are the "swing voters," the segment of the population that the climate denial industry is after. Even if an additional 10 percent of that population became "very concerned," it is likely we would see a lot more political pressure for real clean energy legislation. Migrate 10% of those folks over to "doubtful" and the political reality of getting climate legislation passed becomes far less likely.
The other interesting finding is that most all the population segments agree that energy independence and investments in clean energy are good whether or not they are concerned about the larger environmental issues like climate change and species loss.
Check out the video on the Yale video page.