Reeling from a string of defeats, anti-abortion groups and their Republican allies in state governments are using an array of strategies to counter proposed ballot initiatives intended to protect reproductive rights.

The tactics include attempts to get signatures removed from initiative petitions, legislative pushes for competing ballot measures that could confuse voters and monthslong delays caused by lawsuits over ballot initiative language. Abortion rights advocates say many of the strategies build off ones tested last year in Ohio, where voters eventually passed a constitutional amendment affirming reproductive rights.

The strategies are being used in one form or another in at least seven states where initiatives aimed at codifying abortion and reproductive rights are proposed for the November ballot. The fights over planned statewide ballot initiatives are the latest sign of the deep divisions created by the Supreme Court’s decision two years ago to end a constitutional right to abortion.

This past week, the court issued a ruling in another major abortion case, unanimously upholding access to a drug used in the majority of American abortions, although fights over mifepristone remain active in many states.

The stakes for the proposed ballot initiatives are high for both sides.

Where Republicans control the legislature and enact strict abortion limits, a statewide citizens initiative is often the only avenue for protecting access to abortion and other reproductive rights. Voters have either enshrined abortion rights or turned back attempts to restrict it in all seven states where the question has been on the ballot since 2022.

In South Dakota, lawmakers passed a bill allowing residents to withdraw their signatures on citizen-led petitions. This launched a comprehensive effort by anti-abortion groups to invalidate a proposed abortion rights ballot measure by encouraging endorsers to withdraw signatures.

The South Dakota secretary of state in May labeled as a “scam” hundreds of phone calls from an anti-abortion group the office accused of “impersonating” government officials.

“It appears that the calls are trying to pressure voters into asking that their name be removed from the Abortion Rights petitions,” the office said in a statement.

A co-founder of Dakotans for Health, the organization behind the proposed measure, Adam Weiland, said this is part of “an orchestrated, organized effort across states.”

“The people want to vote on this issue, and they don’t want that to happen,” he said of anti-abortion groups. “They’re using everything they can to prevent a vote on this issue.”

An Arkansas “Decline to Sign” campaign escalated this month after a conservative advocacy group published the names of the paid canvassers for an abortion rights ballot measure effort. Arkansans for Limited Government, the group behind the ballot measure effort, denounced the move as an intimidation tactic.

In Missouri, Republicans and anti-abortion groups have opposed efforts to restore abortion rights through a constitutional amendment at every step in the process.

Missouri’s Republican attorney general, Andrew Bailey, stonewalled the abortion-rights campaign for months last year. Then the secretary of state, Republican Jay Ashcroft, tried to describe the proposal to voters as allowing “dangerous and unregulated abortions until live birth.” A state appeals court last year ruled that Mr. Ashcroft’s wording was politically partisan and tossed it.

But Mr. Ashcroft’s actions and the legal battle cost the abortion-rights campaign several months, blocking its supporters from collecting thousands of voter signatures needed to put the amendment on the ballot.

Once the legal battles were settled, abortion opponents launched a “decline to sign” campaign aimed at thwarting the abortion-rights campaigns’ signature-collecting efforts. At one point, voters were sent texts falsely accusing petitioners of trying to steal people’s personal data.

Republican lawmakers sought to advance another ballot measure to raise the threshold for amending the Missouri Constitution, partly in hopes of making it harder to enact the abortion-rights proposal.

Both anti-abortion efforts failed, and the abortion-rights campaign in May turned in more than double the required number of voter signatures. Now it’s up to Mr. Ashcroft’s office to verify the signatures and qualify it for the ballot.

Meanwhile, opposition groups in Arizona, Colorado, Florida and Nebraska have tried to create their own ballot amendments to codify existing abortion restrictions, though these efforts failed to gather enough signatures in Florida and Colorado.

A strategy document leaked last month shows Arizona Republicans considering several competing measures to enshrine abortion restrictions into the state constitution. Possible petition names include the “Protecting Pregnant Women and Safe Abortions Act,” the “Arizona Abortion and Reproductive Care Act” or the “Arizona Abortion Protection Act.”

The document explicitly details how the alternative measures could undercut a proposal from reproductive rights groups aiming to codify abortion rights through viability, usually around 23 weeks to 24 weeks into pregnancy.

“This leaked document showed a plan to confuse voters through one or multiple competing ballot measures with similar titles,” said Cheryl Bruce, campaign manager for Arizona for Abortion Access.

In Nebraska, anti-abortion groups are countering a planned ballot initiative to protect reproductive rights with two of their own.

A campaign manager of the Nebraska Protect Our Rights campaign, which is intended to protect reproductive rights, Allie Berry, said the competing measures are designed to deceive and confuse voters. She said the campaign is working to educate voters on the differences between each of the initiatives.

“If you’re having to resort to deception and confusion, it shows that they realize that most Nebraskans want to protect abortion rights,” she said.

One counter initiative launched by anti-abortion activists in May seeks to ban abortion at all stages of pregnancy. Called “Now Choose Life,” the petition would grant embryos “personhood.”

Another launched in March would not go that far but instead seeks to codify the state’s existing 12-week abortion ban into the state constitution while giving lawmakers the ability to pass further restrictions in the future.

The petition, called Protect Women and Children, has been endorsed by the national anti-abortion group Susan B. Anthony Pro-Life America and others in the state.

The executive director of Nebraska Right to Life, Sandy Danek, called the petition a “reasonable alternative measure.” She said as “as time goes on and we continue to educate,” the organization will aim to restrict abortion further.

“I see this as an incremental process that we’ve been working on for 50 years,” she said.