This is a prime example why churches need to turn in the 990 tax forms and refrain from any political endorsements like the rest of the non-profits. Once the IRS starts to tax these rule breakers this will stop.
I have a friend who was once an IRS agent in American Samoa. She went after those churches that broke the rules. Most of the time they didn't even know of the rules but they quickly learned, the hard way.
Just to note; FFRF sued the IRS on this twice and won. Under tRump I think they feel they can get away with letting the church's have a free pass.