I would have a hard time believing that those who support abortion rights would be upset by the killing of newborns.
They're not upset at all. People who support abortion loathe children, especially infants.
Liberals engage in this contradictory thinking all the time.
I have relatives by marriage who wanted a child, but were infertile. This couple are very, very politically correct lefties (journalist, college professor types).
While they were on a waiting list to adopt, there was a much publicized incident of a baby thrown in a dumpster. They were highly indignant -- "How could anyone do such a thing!" and "People like that should be shot!"
Yet both of these people are ardent pro-aborts. Oh, and anti-death penalty too.