Sadly, 3rd party candidates in America have an astronomically low chance of ever winning. I won't say it can't happen, but with today's two party system its damn near improbable. Now, if you AGREE with a 3rd party candidate and you vote for him, thats a different story. But to vote for him just because "he's not one of the other two" is none-sensical. I think you need to fully understand what that candidate is running for, what his ideas are etc etc. Too many people think "Well, he certainly isnt Bush!" and then vote just based on those grounds. If you don't know what you are voting for, don't vote.
I totally agree that we need more diversity. That is why the election process we have now NEEDS to be changed. Money caps for how much one can spend on campaigne adds and the like will be one solution. That would make it a fairly equal playing field. I want to see not only republicans, democrats, conservatives and liberals...I want to see socialists, communists and every other form of political ideology in the race. The two party system offers nothing but nothing. There IS no difference between republicans and democrats now a days.