Why is that Christians seemed to be convinced that republicans are against abortions?

Republicans have said time and time again they support roe v wade but personally don't believe in abortion. when it boils down to it the two parties are arguing about when to kill the baby not should the baby be killed. Murder is murder doesn't matter when it is done. SO if you really are against abortion and want to support God's word you wouldn't be able to vote for either candidate. Or has there actually been a republican in the 21st century that has actually enacted or attempted to enact registration to ban abortion completely because that is what the bible would call for ... Why does it seem no one else notices this?