For the two-party system to shift to a multi-party system, the parties outside of the Big Two have to curb some of their nuttier policy planks. For example, Libertarianism. The Libertarian party promotes even less government than Small Government Conservatives. As much as people say they want that, they also want to feel safe in their beds, and they realize that requires money in the form of taxes. Armies and police, etc., are what the American people want. They are afraid of a government that doesn't have the money to support these things. Libertarian dismantling of the government (including the military and police) terrifies most people, even Small Government Conservatives.

I believe the problem is more that the 13th Amendment has changed since 1875. Prior to that, the wording made clear that lobbying is bribery, and thus accepting said is treason. Now, they've had to make new "ethics" laws that include so many loopholes that the ABC Evening News has had reports on how much money Obama's supposedly "small contributor money only" campaign is really a joke. We'll see the same reported next week of the Republican convention and campaign.

Eliminate lobbyists and the money going around, and you might have politicians who actually are in it to serve the public.