I don't know if there's any good indication of that. They were desensitized to them, for sure. It's only been discovered in recent years that Germans were aware of the camps before the end of WWII. And if they knew, it wasn't much. Hitler was popular, no question, but remember the Weimar Republic before his chancellorship was the initial governorship of the Social Democrats, then non-partisans and Centre Party politicians. He was appointed Chancellor. The Nazis never won a majority vote. There was a growing right-wing and nationalistic pulse in Germany that helped give rise to the Nazis, but few Communists and Social Democrats defected to the Nazi Party.
But anyway, the Holocaust and abortion are not similar unless you really stretch how you perceive abortion. Abortion is most often the result of low-income women of color unable to afford children or any more children, or unintentionally produced a fertilized egg due to lack of reliable contraception. A majority of aborted pregnancies were not intended to begin with. Women should have that bodily autonomy to remove a growing fetus if they do not want it. It's not exactly murder because it won't become a person.