US Voting system. Why are there two main political parties?

[Isaiah Bradley]

[ame="http://www.youtube.com/watch?v=s7tWHJfhiyo"]The Problems with First Past the Post Voting Explained[/ame]

the video also provides good/bad of other voting structures

 

[Mr swag]

if you have 3 your pulling from one said that supports your views more. and in turn you will never win an election and never get your agenda done. its surcide

 

[NkrumahWasRight Is Wrong]

divide and conQuer

 

[GulfCoastGhost]

Because a third party covered by media would point out the idiocy of the other two parties

I don't count the "tea party" because they are just crazier than normal republicans and mountain militia men