For the most part...
I will insert a caveat that there is nothing wrong with searching for and electing the next Reagan type politician.
Friedman's point was that by-and-large politicians are almost always acting in self interest (like everyone else) rather than "for the people". Therefore we shouldn't focus all our hopes and efforts on finding that "diamond in the rough" politician that will do the right thing despite popular opinion: It is far more effective to sway the public from the bottom up which will make it natural(politically profitable) for politicians to do the "right thing".
Friedman certainly practiced this method.
Exit Question: Practically speaking, how do we make it politically profitable for the wrong people to do the right thing?
Yes I did name my new dog Milton. I'll let you guess who he's named after :)