Two Party System

I have been trying to figure out why we are in a rut of a two party system. I've found that it is not just because of America's reluctance to vote for a third party, it is just amazing difficult to just get on the ballot. In Illinois a third party has to get 42,000 signatures in just 90 days, which you think that isn't so much but they have to be got by the person running.  Making it pretty difficult to do campaigning at the same time.  Anyway for all those planning to vote don't rule out a third party, just voting for them is saying that you support a wider choice.  And with our candidates being almost identical we really need variety.  

-Zachary