The Legislature on Friday approved a ban on nearly all abortions in South Dakota, setting up a direct legal assault on Roe v. Wade.

Republican Gov. Mike Rounds said he was inclined to sign the bill, which would make it a crime for doctors to perform an abortion unless it was necessary to save the woman's life. The measure would make no exception in cases of rape or incest.

Many opponents and supporters of abortion rights believe the U.S. Supreme Court is more likely to overturn its 1973 Roe v. Wade decision legalizing abortion now that Justices John Roberts and Samuel Alito are on the bench.

Planned Parenthood, which operates the only abortion clinic in South Dakota, has pledged to sue over the measure, which would become law July 1. The clinic does about 800 abortions a year.

The House passed the bill 50-18 on Friday. The Senate approved the measure 23-12 earlier this week.

Under the measure, doctors could get up to five years in prison for performing an illegal abortion.

The governor said he believes it would be better to eliminate abortion in a series of steps, but some abortion opponents want a court challenge that could wipe out abortion in one fell swoop.

"I've indicated I'm pro-life and I do believe abortion is wrong, and that we should do everything we can to save lives," Rounds said. "If this bill accomplishes that, then I am inclined to sign the bill into law."

During debate on the measure, lawmakers were told that an anonymous donor has pledged to give the state $1 million to defend the abortion ban in court. The Legislature is setting up a special account to accept donations for the legal fight.

"I can tell you first-hand we've had people stopping in our office trying to drop off checks to promote the defense of this legislation already," Rounds said.

Opponents of the bill argued that abortion should at least be allowed in cases involving rape, incest and a threat to a women's health.

If a woman who is raped becomes pregnant, the rapist would have the same rights to the child as the mother, said Krista Heeren-Graber, executive director of the South Dakota Network Against Family Violence and Sexual Assault.

"The idea the rapist could be in the child's life ... makes the woman very, very fearful. Sometimes they need to have choice," Heeren-Graber said.