Cato actually has done some studies on the libertarian vote. It went overwhelmingly for George Bush in 2000, but swung about 20 points democratic in 2004. I'm not sure that they've updated the study for 2008, but my gut (and surveys of self-identified well-known libertarians) tell me Obama won the vote.
If you like market economics, don't care if your neighbor is gay, and don't feel like occupying countries on the other side of the world, there is really nobody pandering to you. You tend to move around.
Edit: Here's the paper comparing the 2000 and 2004 elections that I mentioned
Kerry did 18% better than Gore among libertarian voters, despite not having a libertarian bone in his body. Bush won the demographic in both elections, but lost 13% between 2000 and 2004, for a 31 point net swing.
Keep in mind that these are "soft libertarians", people that consider themselves economically conservative and socially liberal, but don't necessarily go around trolling message boards with anarchist philosophy.
2004 seemed to be unusually bad for the republican percentage of the libertarian vote. The only worse year was 1992, when Ross Perot, Clinton, and Bush I all got a third (well, I think 2008 will be bad, too).
If you like market economics, don't care if your neighbor is gay, and don't feel like occupying countries on the other side of the world, there is really nobody pandering to you. You tend to move around.
Edit: Here's the paper comparing the 2000 and 2004 elections that I mentioned
http://www.cato.org/pub_display.php?pub_id=6715
Kerry did 18% better than Gore among libertarian voters, despite not having a libertarian bone in his body. Bush won the demographic in both elections, but lost 13% between 2000 and 2004, for a 31 point net swing.