McClintock is an astute player. If he sees that he doesn't have a chance and that his presence makes it likely that Bustamante wins, he'll probably drop out. If he doesn't burn the Republicans in this race, he'll have a shot at other offices in the future and will probably win. On the other hand, it's a good idea for him to stay in until near the end; if Schwarzenegger flames out for some reason, McClintock will be the backup.