I have to wonder if this is a play towards coal miners, who are part of the conservative base - and they need every vote they can get. Coal is an awful source of power, and a really big source of pollution.

I doubt they really care about coal miners’ actual votes. The US coal mining industry employs fewer than 50,000 people. I live in a major coal producing state and while it was an important industry in my grandparents’ time, these days it isn’t a particularly noteworthy share of our economy.

I would say if it’s specifically about coal at all, it’s more because of the GOP’s tendency toward weird nostalgic obsessions.