Most funding for denier groups comes from conservatives--hard line capitalists who don't want any interference in their capitalistic ventures or anythingbthat cuts into their profits. Any laws that come down on their business interests are, according to them, a left-wing plot to create a socialist government. Any law that interferes with their exploitation of land, the environment or people for their profits is suspect to them. That is what is behind their habit of demonizing of people who see danger in human caused climate change. The capitalists and wannabe capitalists (wjo are legion) will deny anything that has even a whiff of what they see as socialism in it.
There's an almost religious like zeal with the committed contrarians, which includes making serious threats against people who question their belief system on the subject.
http://www.desmogblog.com/2014/03/25/exclusive-climate-change-philosopher-target-abusive-hate-campaign
“DIE you maggot," reads one of the hundreds of emails from climate science deniers that have dropped into philosopher Lawrence Torcello’s inbox in recent days.
“Fortunately, your kind will be marched to the wall with all the other leftist detritus," says another.
Others accuse Torcello, an assistant professor at Rochester Institute of Technology’s Department of Philosophy in the west of New York State, of being a fascist, Stalinist and a Nazi.
The catalyst for the bilious outpouring was an article Torcello had written for The Conversation website arguing there was “good reason to consider" that “the funding of climate denial" was morally and criminally negligent.