I hope after the 2008 election we have learned that though (D) and (R) are far apart in the alphabet, in the political world they are near the same on a lot of issues.
If any want to see where the Republican party is headed, look at the so called Conservative party in the U.K. They are really only conservative in name only. Their party leader, David Cameron, denounced David Hannan (the one who blasted Gordon Brown in the EU parliament) on his criticism of their National Health Service- think universal health care.
Check out Prime Minister's Questions on CSPAN and watch them. You will get a good idea of what is in store for us if we don't stand up for our conservative/libertarian principles and elect those who also believe in them too.