Is our 2 party system a bowl of s*** looking at itself in the mirror?

Off the wall theory: there is not a two party system it is all a dog and pony show and they know who will win before the election ever takes place. It's all a big act to make us believe we have a democracy, after all it seems no matter who is in office it always gets worse. Not saying I believe it...just saying I could either believe that the politicians are dumb because what they do to help makes it worse, or I could believe the first theory. Dumb or a dog and pony show...which is more feasible?