Our country was not actually set up by the founding fathers to be a two-system democracy.
As we found out in the 2000 election our president is supposed to be chosen by the Electoral College. The voters in each state are expected to vote for their representatives to the Electoral College. The people they choose could be for any issue or just "nice" people they trust to represent them wisely when the choice is made. These representatives then meet and choose the President. At some point we started thinking that we were voting directly for the President, but we are still choosing Electoral College representatives that are pledged to vote for us.
The system was rigged when the Democrats and Republics got together and got most states to have the Electoral College representatives pledged to vote 100% for whichever candidate won the "popular" election, thereby maintaining the two-party system. This is how a candidate that doesn't win the popular vote can still win the Electoral College vote -- as Bush did in 2000. This is why the candidates can focus all their energies on the states where the Electoral College vote is in question.
If a smaller party gets say 25% of the vote it doesn't really count at all now, since all the votes in the Electoral College are pledged to the winning "popular" vote candidate. Winner takes all. On the other hand, if the Electoral College representatives voted in percentages according to the popular vote, their vote would be divided. Say California (I don't know the actual breakdown) voted 40% Democrat, 28% Repulbican. 15% Libertarian, and the rest divided among smaller parties, then the 55 California representatives would go to the meeting of the Electoral College and vote that way 40% Dems, 28% Reps, etc. If every state did this then the third parties could have a chance of growing into major forces and voters would want to hear them in debates.
I probably haven't made this clear, but even without financial reform, but by the Electoral College actually voting according to the "popular" vote, third parties could form and exist. It's a little closer to the Parliamentary System.