I won't actively boycott any singers/actors on the basis of their political beliefs - they are as entitled to them as I am. If I could nod along to The Chicks (Dixie Chicks as was) then I have to accept that other artists are entitled to have alternative views.
That said if they choose to add to political commentary then they are fair game for discussion and it will possibly make me less inclined to download albums/films.
I think politics is quite complex in Nashville. It's a blue city in a red state. I imagine most artists play to their core base.