Another significant difference is that coal is concentrated in states that even though they have almost no population still wield 2 senate seats. This is one of the, if not the reason that coal continues to thrive.
You should go read about the Battle of Blair Mountain and the Coal Wars. Big Coal more or less committed genocide in Appalachia and not only got away with it but had some assistance from the US government. That's how powerful they are. The number of senators these states have is pretty irrelevant in the grand scheme.