There are Catholics who are fixated on 'Social Justice' issues, and consider the Democrats much more compassionate on them than Republicans. These issues would include housing for the poor, food for the poor, education for poor children, etc. They can't see that Republican solutions would be better for poor people, because they're not designed to KEEP those people in poverty. Democrats declared a War on Poverty in the 60's, which they lost long ago. Democrat policies are designed to keep people poor so they'll continue to vote for Democrats, so they'll keep the gravy train going.
Those 'Social Justice' Catholics look at abortion as just one issue among many, and don't think it's any more important than taking care of folks who are already here. They also tend to be anti-war, so they use the War on Terror as a reason to vote against Republicans.
I agree with you and the premise of the title is absurd. There is NO issue on which the Democrat solution is preferable to the Republican solution. Therefore, the author has little credility. He is telling Catholic voters that he understands that Democrats are correct on many issues but they’re wrong on abortion and therefore they should vote against the Democrats.