Constitutional protection of the woman's decision to terminate her pregnancy derives from the Due Process Clause of the Fourteenth Amendment. It declares that no State shall "deprive any person of life, liberty, or property, without due process of law."
The legal approach and PR approach don’t need to be the same. When Feinstein says Roe is a super precedent, it seems like a good opportunity for Rs to point out that Roe leaves the option open that the fetus is a life that deserves protection of the state as much as the mother.