CatholicCitizens.org: A Brief Catechism for Catholic Voters from EWTN
Catholic Citizens of Illinois posts a brief Catechism for voters written by Fr. Stephen F. Torraco, PhD . Fr. Torraco posts in a "question-answer" format that makes comprehension easy. Here is a brief example: 4. If I have strong feelings or opinions in favor of a particular candidate, even if he is pro-abortion, why may I not vote for him? As explained in question 1 above, neither your feelings nor your opinions are identical with your conscience. Neither your feelings nor your opinions can take the place of your conscience. Your feelings and opinions should be governed by your conscience. If the candidate about whom you have strong feelings or opinions is pro-abortion, then your feelings and opinions need to be corrected by your correctly informed conscience, which would tell you that it is wrong for you to allow your feelings and opinions to give lesser weight to the fact that the candidate supports a moral evil. This is essential moral theology and worth reading . I&