Your conceptualization of how the world works and mine are so not on the same page, they aren't even in the same book.
So while what you say is no doubt true, it's got nothing to do with what I'm talking about. I'm not expecting universal health care by June of next year or something.
You start by just getting people to say "Yeah, you know, that makes sense. I would support that." And when enough people can agree with that idea, eventually you get candidates who say "I have this terrific idea (parrots back to the world what the world is already saying is a good idea)."
If there were a general consensus that this is something all Americans like, you can bet money we would have a presidential candidate who not only supports the idea but already has a well-thought-out blueprint developed for how to implement it. In fact, you would likely have two candidates competing for your vote based on the idea that "My universal health care plan is better than theirs! Vote for me, Joe Schmoe, the guy with the better universal health care plan!"