This is another one of those instances where people tend to vote against their own best interests, like those of Jewish derivation voting for Democrats despite the benignity towards terrorism of that party.
Entrenched habits die hard, and I noticed it among Catholics of Pennsylvania and New Jersey when I lived there--and of course there's the sordid example of Catholics in Massachusetts constantly voting for Vast Teddy and the other crooks and felons there.
When Richard Nixon first made inroads into both the Jewish and Catholic vote in 1968 and 1972, it was commonly assumed, I suppose, that winning the hearts and minds of these people would be quick, but forty years of elections has shown only mild erosion, just a little tiny bit more, each passing election, rather than a major avalanche towards Republicans.
I have no idea why this is; progress, but only progress at the speed of a glacier.
As for abortion, the issue of abortion is not likely to go away. Sometimes it waxes and wanes, but it's always there. Sometimes it's a hot-button issue, other times it's a warm-button issue, and it's there.
We are never going to do away with abortion period, but I suspect subterranean resentment at that the abortion enthusiasts have had things their way much too long; the whole loaf, the whole thing.
For some reason, abortion enthusiasts consider the "right" to an abortion unconditional and unlimited--at the same time the rights of free expression and speech, the rights of religious (or anti-religious) practice, the rights of property, the rights of justice, while broad and vast, are NOT unconditional and unlimited.
Something's changing here, but it's happening imperceptibly. All one knows is that it's changing.