WASHINGTON (AP) — For the second time in three months, the national debate over reproductive rights focuses on Ohio as voters decide Tuesday whether to amend the state Constitution to protect access to abortion services.

The measure has become one of the nation’s highest-profile contests on the ballot this year and is the latest state-level skirmish over the issue since the U.S. Supreme Court overturned Roe v. Wade in June 2022.

The proposed state constitutional amendment, labeled “Issue 1” on the ballot, would establish the right to “make and carry out one’s own reproductive decisions” on matters including abortion, contraception and fertility treatment. It would also allow for abortions to be banned once it has been established that the fetus can survive outside of the womb, unless a physician determines that continuing with the pregnancy would endanger the patient’s “life or health.”

Abortion rights supporters have had a sizable fundraising advantage throughout the campaign, according to campaign spending records, but opponents of the measure nonetheless have been active in trying to frame the issue for voters. Misinformation about the proposal has spread in TV ads and online. Backers of the amendment have also criticized wording changes to the language that appears on ballots.

In August, voters defeated a separate proposed state constitutional amendment that did not specifically mention abortion or reproductive rights but attracted national attention from activists on both sides of the issue. That proposal would have required future changes to the state constitution to receive at least 60% of support from voters to pass, rather than a simple majority. Had that measure passed, it would have made it more difficult to approve Tuesday’s proposal on abortion.

In 2022, 59% of voters in Ohio’s midterm elections supported abortion being legal in most or all cases, according to AP VoteCast.

Also on Tuesday’s Ohio ballot is a statewide ballot measure to legalize recreational adult use of marijuana.

Here’s a look at what to expect on election night:

ELECTION DAY

The statewide election in Ohio will be held on Tuesday. Polls close at 7:30 p.m. ET.

WHAT’S ON THE BALLOT

The Associated Press will provide coverage for two statewide ballot measures: Issue 1 on abortion rights and Issue 2 on marijuana legalization.

WHO GETS TO VOTE

All registered voters in Ohio are eligible to vote on the two statewide ballot measures. The deadline to register was Oct. 10. Ohio does not allow Election Day registration.

DECISION NOTES

The Aug. 8 statewide ballot measure vote provides a reasonable baseline estimate of support for Tuesday’s proposed amendment on abortion. In that contest, 57% of voters supported the position generally backed by abortion rights advocates, while 43% sided with the position generally adopted by abortion rights opponents.

An AP analysis of the August vote results showed that a significant number of Republicans sided with abortion rights supporters on that proposal. For example, the pro-abortion rights position carried all but two of the 17 swing counties that Donald Trump won in 2020 with between 50% and 62% of the vote, a pattern that the “No” side would need to shift substantially to win on Tuesday.

Victory for the “Yes” side, the position backed by abortion rights supporters, would mean replicating that performance in places like Cincinnati, Dayton and northern Ohio, where Trump won in 2020.

The AP does not make projections and will declare a winner in a ballot measure only when it’s determined there is no scenario that would allow the trailing side to close the gap. If a race has not been called, the AP will explain why and will continue to cover any newsworthy developments.

In Ohio, statewide ballot measures with a vote margin of 0.25% or less are subject to an automatic recount. Voters may also request and pay for recounts for contests with a larger vote margin. The AP may declare a winner in a measure that requires an automatic recount if it can determine the lead is too large for a recount or legal challenge to change the outcome.

WHAT DO TURNOUT AND ADVANCE VOTE LOOK LIKE

As of June 16, there were 7.9 million voters registered in Ohio. The state does not register voters by party.

For the Aug. 8 statewide ballot measure, turnout was 39% of registered voters. It was 51% in the 2022 congressional midterm general election.

By the end of October, almost 385,000 voters had cast ballots before Election Day, 61% cast early in person and 39% cast by mail.

In August, 23% of voters cast their ballots before Election Day. In the 2022 general election, it was 35%.

HOW LONG DOES VOTE COUNTING USUALLY TAKE?

In the Aug. 8 ballot measure election, the AP first reported results at 7:35 p.m. ET, or five minutes after polls closed. The election night tabulation ended at 1:51 a.m. ET with about 99% of total votes counted.