climate change denier on capitol hill. >> it's a snowball. >> reporter: oklahoma senator james inhofe. >> the past hour and a half or so, i've offered compelling evidence that catastrophic global warming is a hoax. >> reporter: inhofe is a staunch opponent of environmental regulations. and when in charge of the senate's environment and public works committee, he held hearings challenging climate warming science. at his side, whispering in his ear, helping to direct questioning, lining up witnesses, was wheeler. capitol hill sources with intimate knowledge of his involvement tell cnn wheeler was the top man in charge and a driving force behind his boss' climate change denying agenda. five former inhofe staffers now work beside wheeler at epa, including his chief of staff, his principal deputy assistant administrator, his assistant administrator for enforcement and compliance, a senior adviser for policy, and an associate