And is it his complaint, or did it originate somewhere else?

Civil liberties have more to do with real individuals than with corporate individuals. Did the commentator complain to the Representative, who then when to the station on behalf of a citizen?

I'm assuming that this is over a political expression on the air.

If he threatened the station with immediate action with a view to intimidate, he has stepped waaay outside acceptable boundaries and needs to hear a few thousand well-chosen words from the party leadership. He could also be served with a few thousand well-chosen words by the station's attorney.

If he threatened the station with review of its license in conjunction with a complaint from a citizen alleging, say, censorship of protected speech and/or unfair labor practices, well, that's a little different.

If this is considered more evil because he's a Democrat, that's a whole different problem, and it's not his.

If you have more details, I can give a more informed opinion.