If you postulate the Right is made up of rational, intellegent people who have a well thought out ideology and belief system and they make up about 40% of the population, and the Left is similar in size and intellegence, you have 40% of the people vs 40% of the people.
The people who choose the elected officials are the remaining 20%, you know the morons who have given no thought towards their belief system, have no understanding of the world around us, whose education on government comes from watching Friends reruns.
In other words, our elected officials are chosen by the stupidest people on the planet...