If Bush loses, it will not be because any third party "drained" votes from him.
90 million people didn't vote in the last election. Compare that to the 1 million Libertarian voters. If Bush pushed Libertarian ideals, or took any third party issue and made it his own...If he had a genuine interest in reducing government power (rather than growing government at 13% a year), he would blow Kerry out of the water. People who loathe the big government we've been getting under democrats and republicans would finally have a reason to vote FOR him...and they would.
The sad fact is Bush hasn't demonstrated any interest in reducing the size of government. On the campaign trail, he has actually bragging about how much he has increased it's with his new $600 billion medicare entitlement and other massive spending bills.
If a principled conservative can't vote for Bush this year, it really hasn't cost Bush anything. Bush has simply failed to EARN that person's vote, and never really had it in the first place.
BS these third party types do vote and can enable Democrats. Can't get any worse than that.