Except that's clearly wrong, as evidenced by this very story. Joe reads reddit and hears about SOPA. Joe tells his rep he doesn't like SOPA. And his rep flips. QED.
The bug in your logic is that "tribal affiliation" is, in fact, an "issue" Joe cares about. You don't think it's an important issue, and probably don't like his affiliation anyway, but it is and he's going to vote on it. But it isn't the only issue.
Basically: you can't expect to "educate" Joe to think like you do. Education can't cure Christiantity, etc... But you can tell him about stuff he cares about. Real people care about SOPA, they just don't know the details. That is something that can be fixed.