Cardinal Ratzinger mentioned “proportionate reasons” in his letter to Cardinal McCarrick regarding why some voters may be able to vote for an anti-life politician. Just what are those proportionate reasons? Fr. Stephen Toracco has a Brief Catechism for Catholic Voters on the EWTN site that, among other things, discusses those reasons. Read especially nos. 6 & 9, for what he means.Here is one for example:
What if one leading candidate is anti-abortion except in the cases of rape or incest, another leading candidate is completely pro-abortion, and a trailing candidate, not likely to win, is completely anti-abortion. Would I be obliged to vote for the candidate not likely to win?
In such a case, the Catholic voter may clearly choose to vote for the candidate not likely to win. In addition, the Catholic voter may assess that voting for that candidate might only benefit the completely pro-abortion candidate, and, precisely for the purpose of curtailing the evil of abortion, decide to vote for the leading candidate that is anti-abortion but not perfectly so. This decision would be in keeping with the words of the Pope quoted in question 8 above.