That means that you aren't going to get people who aren't already diehard Dems or Reps.
Which is irritating, because they tend to be more extreame than most.
Sencondly, mostly due to the media, we aren't interested in actual leadership ability, just the *appearance* of actual leadership ability. Same with the issues. For the most part, people don't pay attention to how people vote, just what they say come re-election time. We could have paid actors doing drama in washington and I don't think anyone would notice.
Sad, but true. When the big issue during an election is same-sex marriage (and not the economy, war, terrorism, and the like) something is wrong.
The third thing is that people tend to all vote in their own best interest. So in a nation where most people are rich, taxes are to be cut and all that wasteful welfare has to go. Where people are poor, the social welfare state must get bigger and better, damn the cost. If you live in the city, you vote for environmental issues, but if you live in the country, then you vote to cut down the trees and sell the wood. So if you're in the minority and really need the legislation to pass, it probably wouldn't happen.
It's not just who is in the majority, it's who has power. The poor and middle-class outnumber the rich, but due to donations, ect, the rich have a disproportional influence. Also, they are more likely to pay attention and vote.