He doesn’t have to be an Einstein to know that this guy is a Republican. So, he shouts over to the bartender so loudly that everyone can hear, "Drinks for everyone in here, bartender, but not for the Republican."
Soon after the drinks have been handed out, the Republican gives him a big smile, waves at him, then says, "Thank you!" in an equally loud voice. This infuriates the union boss, so he once again loudly orders drinks for everyone except the Republican. As before, this does not seem to bother the Republican. He continues to smile, and again yells, "Thank you!"
Frustrated, the union boss asks the bartender, "What the hell is the matter with that Republican? I’ve ordered three rounds of drinks for everyone in the bar but him, and all the silly ass does is smile and thank me. Is he nuts?"
"Nope," replies the bartender. "He owns the place."