When he professed his conviction that Jesus was the Son of the living God he did not quietly whisper to Jesus to come aside and tell Him privately. He said it unashamedly in front of all the rest of the disciples. When he denied Jesus, he did it cursing. And when it became known to him that he was to be crucified like his Master he requested that he be crucified upside down. Bush is moderate because he permitted a practicing homosexual to address the GOP convention and Gore is moderate because he refused to allow a congresswoman who supported a Playboy fundraiser to speak to the Democratic convention.
Candidates are interested in votes.
Plain and simple. To garner the most votes the candidate must appeal to the widest spectrum of voters possible. Demographics such as gender, race, age, socio-economics, and ideologies all play important factors when attempting to appeal to the greatest number of potential voters. It is sort of like the old bell curve system in grading. A few will do badly.