Members of say an ironworkers union are really only interested in how much they are going to get paid and long-term benefits. The union leadership may be interested in political agendas but not the members themselves, this is not the case with the NEA.
It was the industrial and trade unions who voted for Reagan and became the core of the Reagan democrats. It seems that the coal workers voted pretty heavily for Bush as well.
A friend of mine worked at a union shop in Dexter Michigan during the 2000 election. He said his union steward was supposed to pass out pro Gore literature but always threw it in the trash and told them they could get it from there if they wanted it. LOL