When I was in high school I once attended a Ralph Nader political rally at the Target Center in Minneapolis. He and the other speakers railed against the influence of money in politics, the common theme being that when voting for Democrats or Republicans you are often voting for the lesser of two evils. The choice of door number one or door number two feel more like a game show then a success of democracy. I left with a T-shirt that depicted George W. Bush and Al Gore as dinosaurs and Ralph Nader as a caveman.
The current status of our federal democracy, this combining of our large and varied country into one ruling body, is in shutdown. I like to chalk this up to the failure of voters to grasp their option of choice. The two party system sets up a rivalry similar to that of two crosstown rivals, who hate each other greatly but have more in common with each other then any other teams they might face off against. That is why when the subject of National Defense, or in the United States national offence. both groups tend to agree with each other because of the idea of different aka (foreign) countries are much more different then US. The lack of choice stems from the low turnout in primary elections where per-capita eligible voters show up less then 20% for primary voting.
Then when the 'real' election comes about people see the only options as either Democrat or Republican, because other political candidates are seen as throw-away votes. And the only thing worse then voting for the candidate who loses is voting for someone who never had a chance anyways. People also have the false sense of personal winning when the candidate they voted for wins. "We won!" people will shout on election night, when in truth they didn't win anything. The candidates will have to run for re-election soon and while in office they will have to listen to the lobbyists of the groups that donated and supported their election campaign, if they ignore those lobbyists they risk losing financial support from previous groups in their re-election campaign.
The idea is that there is enough variation within the two parties to allow for a large and open dialogue. That the use of money in elections doesn't harm democracy.