Schiavo's active involvement in politics is, primarily, an act of self-justification. In our predominantly secular society, politics is the religion of the secularists, and the state is their god, so MS is paying homage to the gods of this world through the supreme religious act of this age -- participation in politics. And by seeing candidates elected who agree with his perverted sense of morality, he's justified or at least vindicated in his beliefs (in his mind), and the god of this age shines up at him, and blesses him.
Since the article indicates that he works 36 hours a week at his "day" job, the PAC and his other political activities may be a means for dear Michael to earn a few bucks too. Somebody with deep pockets may be picking up the tab for him a la Crazy Cindy.