Let us first note that we are talking about less than 500 abortions a year where rape or incest in concerned.The overwhelming number of pro-life canidates in this country support abortion only in the cases of abortion, incest and direct threat to the Mothers life. The fact they are not in perfect alignement with Church teaching does not gives us Catholics Carte Blanche to vote for one who suports abortion in all circumstances just becuase we like his views on other issues.
Bishop Garcia the Churchs position very well:
There is only one thing that could be considered proportionate enough to justify a Catholic voting for a candidate who is known to be pro-abortion, and that is the protection of innocent human life.
That may seem to be contradictory, but it is not.
Consider the case of a Catholic voter who must choose between three candidates: candidate (A, Kerry) who is completely for abortion-on-demand, candidate (B, Bush) who is in favor of very limited abortion, i.e., in favor of greatly restricting abortion and candidate (C, Peroutka), a candidate who is completely against abortion but who is universally recognized as being unelectable.
The Catholic voter cannot vote for candidate (A, Kerry) because that would be formal cooperation in the sin of abortion if that candidate were to be elected and assist in passing legislation, which would remove restrictions on, abortion-on-demand.
The Catholic can vote for candidate (C, Peroutka) but that will probably only help ensure the election of candidate (A, Kerry).
Therefore the Catholic voter has a proportionate reason to vote for candidate (B, Bush) since his vote may help to ensure the defeat of candidate (A, Kerry) and may result in the saving of some innocent human lives if candidate (B, Bush) is elected and votes for legislation restricting abortion-on-demand. In such a case, the Catholic voter would have chosen the lesser of two evils which is morally permissible under these circumstances.
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What the Church teaches is we can not let the perfect be the enemy of the possible. We can not let the misguided thinking of a canidate who supports perhaps 500 abortions a year lead us to rationalize voting for a canidate who supports even less restrictions on abortion.