The sheeperal support it because they are “good people” who want everyone to have affordable healthcare... at least that’s what they say. They’re really about the sense of self-righteousness they get for taking this position. They don’t even WANT to know whether it “works” or not.
Of course, the other side of the coin, the elitist control freak fascist liberals, know the goal is CONTROL. And in that sense, it’s working toward being a HUGE success.