It is my belief that if every person who is fed up with the current one party with two heads
system actually went out and voted for any of the other available (read "third party") candidates, the winner would almost certainly turn out to be one of the "third party" candidates.
I think the main reason so low a percentage of eligible voters actually get out and does so is apathy, the notion that their vote doesn't count. This apathy stems from having had an endless stream of soundbite producing talking heads to vote for, all hype and no substance. Maybe the parties would start nominating real people with real morals and the ability to tell the truth and stand up for what they really believe in instead of what the party's steering committee told them to say they believed in if we, the voters, started rejecting the dipshits they put in front of us every two years. I think low voter turnout is in fact a symptom of this rejection, but the parties don't see it this way, and in fact, low voter turnout actually helps them.
Even worse than apathy is the concept of wasting ones vote. What utter bullshit. To vote for one of the mainstream candidates in some sort of "lesser of the two evils" mindset is nothing more than an admission of ones sheephood. I remember back to some of the post-balloting exit polls during the '92 election when Ross Perot ran, and the surprising thing to me was the sheer number of people who said they would've voted for Perot if they didn't think they'd be "wasting their vote". If they'd all have voted for him like their intellects told them to do instead of that sorry excuse for a human that we currently call our President or the other asshole, the last eight years would've certainly been different for America. If you don't like what either of the idiots running for President have to say, Don't Vote For Them!
So, I don't really believe that voting third party sends a message to the politicians, because they and their spin doctors aren't really listening to the American People anyway, but they will listen when a thrid party candidate beats them and they have to pack their stuff and move home.