Life is life. No one should have the right to stop life.
"All that is necessary for the triumph of evil is that good men do nothing."
Our duty as Christians is not only to vote in line with our consciences. Our obligation is to fight against evil. Abortion is the most heinous of sins and yet most Christians are not willing to do anything to stop it. Slowing abortion is not a matter of overturning a law. Abortions will slow when good men care enough about the unborn to risk time and resources to help individual women.
Find your local Crisis Pregnancy Center and volunteer.