Party Loyalty.
Its better to get inside a party and help to direct change, then to bitch about it.
If all of these "true" conservatives were involved in the Republican party then the party would have never become the Neo-con party it is now.
Same goes for the Democrats. They haven't won since Clinton because their base in the party is week and 92 in small party was won because of Perot. Bring back FDR and they would have a better chance of winning. There will be no New Deal with Obama.
Bush 2 was the last president since Bush 1 to win over 50% of the vote. Clinton never did.