Republicans are not good at tactics.
If the roles in abortion were reversed, the Leftists would have assured us that NOBODY thinks abortion is wrong in cases of rape and incest, we just want to limit those abortions for other reasons. They would have cajoled us into laws that sensibly limit discretionary abortions, until we were all used to them. And THEN they would have rolled out the arguments against abortion in rape and incest cases, with full, moral outrage -- as though they had never taken a different position.
Leftists are dishonest; but it's not dishonest to take an incremental approach against abortion. Seventy percent of the US favors limiting abortion to cases of rape or incest, or where the mother's life is endangered.