The problem with 3rd party is they want to start at the top.
The only way to the top is to start at the bottom. Any real chance is to win state seats then work into congress then you stand a chance to be top dog. But with the country living a fast food life everyone wants the gold watch first.

Clinton = never
Obama = hope and change, but what the change is I havent heard yet(other then get out of the war)
McCain = Whatever lesser of 3 evils. Kinda sad.