(Bloomberg) -- Ohio voters enshrined abortion rights in their state’s Constitution, a boon for Democrats running on the issue and complicating Republicans’ approach to the 2024 elections.

The amendment was adopted by a margin of 56% to 44% with about 90% of the vote counted in Tuesday’s general election in Ohio, the only state with an abortion issue on the ballot this fall, according to the Associated Press. The amendment prevents the state from interfering with reproductive decisions up to about 23 weeks of pregnancy.

Supporters have said the amendment takes important decisions away from the government and was needed after Ohio Republicans enacted one of the most restrictive bans in the country in 2019. That law, which has been held off pending a legal challenge, bans abortions after about six weeks — before many women know they’re pregnant with no exceptions.

“Ohio voters said loud and clear tonight, ‘Yes, we support reproductive freedom and abortion access,’” Lauren Blauvelt, co-chair of the coalition that sought the amendment and executive director of Planned Parenthood Advocates of Ohio, said at an election night gathering in Columbus. 

Ohio was the latest state to back abortion rights after the US Supreme Court overturned the 1973 Roe v. Wade decision last year. Anti-abortion referendums were defeated in Kansas, Kentucky and Montana last year, and rights measures passed in California, Michigan and Vermont. Earlier this year, a Wisconsin state supreme court candidate who pledged to back abortion rights won by a wide margin with unusually high turnout.

Passing the amendment in Ohio, a state that Donald Trump won easily twice, shows abortion can be a motivating issue for Democrats while animating many Republicans, especially suburban women, in the presidential race and other key 2024 elections, according to Doug Sosnik, a veteran Democratic strategist. The issue was passing in several Ohio counties that Trump carried in 2020.

“It’s like a freight train that’s picked up even more speed on the issue,” Sosnik said.

President Joe Biden said in a statement on Tuesday night that voters in Ohio and across the country have rejected “extreme abortion bans” sought in a Republican agenda that is out of step with a majority of Americans.

“Tonight, Americans once again voted to protect their fundamental freedoms – and democracy won,” Biden said.

Mark Caleb Smith, director of the Center for Political Studies at Cedarville University in Ohio, said Issue 1 supporters benefited because opponents were outspent on advertising, $24.6 million to $16.3 million, according to AdImpact. Another ballot issue to legalize recreational marijuana likely helped encourage turnout of younger voters, supporters said.

Abortion opponents, led by Republican Governor Mike DeWine, had argued that Issue 1 was too broad and “goes too far” by allowing abortion at any time up until birth.

And Marjorie Dannenfelser, president of Susan B. Anthony Pro-Life America, said in a statement that “moving forward in states where abortion will be on the ballot in 2024, pro-life, pro-woman coalitions will need to devote more resources to compassionate pro-life messages for women and their children, combating the campaign of fear from the other side.” 

Supporters accusing opponents of waging a “disinformation campaign” to defeat the measure, including approving ballot language that used the term “unborn child” instead of “fetus.” Ohio Republicans also tried using a special election in August to raise the threshold for passing an amendment to 60% from a simple majority. Voters soundly rejected it.

Ohio Department of Health data show that the vast majority, or 89%, of the 18,488 abortions in the state last year were performed before 13 weeks of pregnancy, and only 107 — or 0.6% — were done at 21 weeks and over. Often in those cases, the fetus couldn’t survive or the mother’s life was in jeopardy.

Michael Bloomberg, the founder and majority owner of Bloomberg LP, the parent of Bloomberg News, gave $1 million to the campaign supporting Issue 1.

(Updates with comments, from fourth paragraph.)

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