Chesapeake Energy Corp. CEO Aubrey McClendon could be under fire over his controversial financial stake in the company’s oil-and-gas wells, but he’s declaring victory in a bigger battle: his campaign against coal.

McClendon has long touted natural gas as a cleaner alternative to coal as a power source. The effort has included pouring money into the Sierra Club’s anti-coal plant efforts and funding eye-catching 2007 ads declaring “coal is filthy” that drew tough words from coal-state lawmakers.