The term "pro-life" is currently being redefined, slowly and subtly. Abortion is the one issue where ground has been lost in the culture war by the forces of modernization. In fact, current polls show that most don't support abortion in the US, the exception being in cases of rape, endangerment of the mother, etc.
So, in order to address that, "pro-life" will soon come to mean anti-death penalty and pro-social welfare. It's somewhat faciliated by elements in the Christian realm that agree with the traditional pro-life abortion stance, but also desire to see the pro-life statement further extended to the death penalty.
I'd say it's more a case of "my opinion matters the most" syndrome. If you don't like the field of debate, you simply begin to redefine them these days...
