Ludology Bonus Episode - Voting

In this GameTek from 2008 Geoff discusses voting in general, and the specific voting system in the United States. Do the rules in the United States lead towards a two-party system? Or is it possible for a third party to have a shot at the presidency? (Note: This podcast is not endorsing any particular party or candidate. It is merely a discussion of the 'rules' of voting and how that may impact results)