Republicans (conservatives, generally) have limited empathy. Relatively few people will every have the need to seek an abortion as a percentage of the population - only half are even eligible. The lack of empathy means they do not consider that it is a problem for them until it actually happens to them. For the base it’s a litmus test which allows the candidate to do or say almost anything and still guarantee a vote; for the rest who have never had to seek or don’t expect to need to seek an abortion, it’s a non-issue and they can cite more (American) moderate right policies like lower taxes and less regulation as their driving force.