That is also when Mr. Rapert won a seat in the State Senate to represent this city just north of Little Rock. His victory was an especially resonant and personal one. His opponent, Linda S. Tyler, 64, a popular moderate Democrat, was the person he blamed most for blocking a more restrictive anti-abortion proposal the year before, when he was a freshman legislator.

The public health committee that Ms. Tyler then chaired in the House refused to advance his 2011 bill even after it had passed the State Senate. In the November campaign, he implied that Ms. Tyler was personally responsible for allowing more deaths of unborn babies.

“My opponent killed 10 pro-life bills,” Mr. Rapert said of Ms. Tyler in an interview at the Capitol on Friday.

“He characterized me as a far-left liberal,” Ms. Tyler recalled last weekend at her home in Conway. “But I feel I represent the conservative values in my district.”

Ms. Tyler, a former human resources executive and small-business owner, said that a majority of her committee members had declined to act on bills they regarded as unconstitutional. She said that she has never called herself “pro-choice” and that she had voted to ban late-term abortions. But in the end, she said, abortion should be a decision involving a woman, her family, her faith and her doctor.

The law will take effect 90 days after the legislative session ends in the coming weeks. The American Civil Liberties Union and the Center for Reproductive Rights have promised a rapid legal challenge; on the other side, Liberty Counsel, a Christian law firm linked with Liberty University in Virginia, has offered to help Arkansas defend the law on a pro bono basis.