In the state and local levels of our federal republic, it is possible and has happened. You can make a case that a vote for a third party in the federal elections is like you are not there and is a waste, however, in the other levels of governance it is incorrect to say so.
A Libertarian dog catcher, or a Constitution Party school board member doesn't cut it. No fringer is going to be elected president, or even a Senator, in your lifetime! The people of Minn. are still ashamed and sorry that Jesse Ventura was ever elected governor.You think that'll ever happen again,any time soon ? LOL
I have to disagree with you on the first part. I think that it has to affect the candidates somewhat when they see growing numbers of people either not voting or voting for a third party. Even Rove has stated the importance of getting certain parties on the side of Republicans in the 2000 election. Say a large group of the electorate, evangelicals (Christians) for example, were to hypothetically sit out more than one election, what would happen? How would a candidate try to regain that vote?
Eventually, and I'm not saying necessarily in 2004, this is going to happen. A protest vote from the right will eventually occur to the point that it will make the Republican party realize they can't continually keep moving to gain votes.