Abortion rights advocates claimed victory on Wednesday after US voters sided with protecting access to the procedure in several ballot initiatives, in a rebuke of the Supreme Court's June decision to overturn nationwide access.
Voters in California, Vermont and Michigan strongly endorsed proposed state constitutional amendments guaranteeing the right to abortion.
And in Republican stronghold Kentucky — where abortion has been outlawed since the Supreme Court ruling — voters rejected an amendment to the state charter that would have, in effect, made it impossible to challenge the state's ban.
In Montana, the fifth state with an abortion measure on the ballot, a preliminary count indicated voters there also opposed legislation hostile to the procedure.
Analysts suggest progressive voters were motivated to turn out for Tuesday's midterm elections in part by the conservative-majority Supreme Court's ruling overturning Roe v Wade, the 1973 case that established abortion as a constitutional right.
The court's decision pushed the issue to states to decide and anti-abortion groups mounted strong campaigns to ban or severely restrict the practice.
About 15 states instituted full-scale bans, which the White House denounced as “radical” attacks on fundamental rights.
“Across the country last night, we saw an unmistakable repudiation of the Supreme Court's decision to overturn Roe,” said Nancy Northup, president of the Centre for Reproductive Rights.
“From Kentucky to Michigan to Vermont to California, Americans want their right to abortion protected.
“People are energised and they do not want politicians controlling their bodies and futures.”
Planned Parenthood said the verdicts proved that the issue motivated voters.
“The pundits were wrong. Abortion rights was the game changer this election,” the organisation said.
Anthony Romero, executive director of the American Civil Liberties Union (ACLU), said the votes in the five states showed that voters will “stand up for the ability to access essential abortion care in overwhelming numbers”.
He said the results validated the ACLU's efforts to support state-based initiatives to protect access to abortion.
But, he added, their “work is far from finished on the federal level or in states across the country”.
The votes in California, Michigan and Vermont for constitutional amendments to protect abortion rights were not surprising: all three are firmly Democratic states and the electoral verdict was clear.
In conservative Kentucky, however, the ballot measure supported by anti-abortion groups was rejected by a relatively narrow 52 per cent to 48 per cent margin.
The Guttmacher Institute, which advocates abortion rights, acknowledged that the procedure will remain prohibited in Kentucky after Tuesday's vote.
“While abortion is still banned in the state except in very narrow circumstances, defeating this measure is a significant win and could set the stage for future progress on abortion rights,” it said.