What sets the bounds of discourse is where those swing voters are. Of course, the general corporate media makes all sorts of radical positions unlikely to appeal to those swing voters, although that is changed in between elections by steady progressive organizing.
Bush and Gore did not come out against racial profiling in the debates because of Nader or any other outsider campaign, but because of non-electoral organizing by anti-police brutality activists who forced the issue onto the national consciousness to the extent that even swing voters recognized its repugnance. Same with a range of other issues.
Nader is not bringing the anti-corporate issues into the national debate. He is riding the extra-electoral organizing from Seattle to DC that raised those issues in the national consciousness.
The interesting issue is not that national Presidential campaigns are fought at the margins of swing issues, but what issues have been forced onto the national agenda in between elections. The reason I have such scorn for third party campaigns is that they operate under the illusion that they are the tail wagging the dog of public discourse, that if we just run a pure candidate, that is what is needed to alter the debate in our society.
But the real strategy should be reverse. If we organize passionately between elections, in our communities and in our workplaces, then national consciousness of those swing voters will shift and the elections will be fought based on those more progressive issues. Who the candidates are and what party they come from is far less relevant than the electorate's consciousness, especially in a system of primaries which shapes even the nominees based on that consciousness.
You want to change the bounds of acceptable discouse in elections? Change them before the elections even start.
-- Nathan Newman