Experts say it is not likely Trump’s shifting position will prompt abortion opponents to defect to Harris’s camp.

But, they warn, there is a real risk that some could stay home on election day, rather than support Trump.

For instance, one prominent anti-abortion rights activist, Lila Rose, has urged her followers on social media to not vote for Trump unless he takes a harder stance on abortion. Rose’s Facebook page alone reaches more than 1.1 million followers.

“This is going to be a very close election, and so if even a small percentage of those base voters do stay home, it could be a big deal,” said Ziegler.

“There is a subset of folks in the Republican Party who are primarily socially conservative, and there’s going to be some fraction of those people who are actually upset. ​​I don’t expect that to be most people, but it could be significant, even if it’s a small number.”

It’s also unclear how swing voters will respond to Trump’s abortion mixed messages.

An August poll from The New York Times and Siena College found that, in seven battleground states, a “growing share” of voters identified abortion as their top election issue.

But Hansen at the University of New Mexico pointed out that other issues still outrank abortion in many swing states.

“I don’t think it’s unimportant. It’s just really hard to gauge how important it will be,” Hansen explained.

“Unless you’re directly impacted by the overturn of Roe v Wade, you’re more likely to make your decision on other dimensions. And the economy is a big one this year.”

Nevertheless, research by PhD candidate Layla Brooks at Emory University found that abortion can be a powerful incentive for women to go to the polls.

Brooks analysed data from the 2022 midterms and found that women vote in higher numbers when abortion is a major election issue — for example, when an abortion-related measure is on the ballot.

“The results I have so far show that women did turn out to vote more in states where abortion policy was coded as highly important,” she told Al Jazeera.

Brooks personally hopes that the backsliding on abortion rights will motivate more women to vote.

“I would hope that this would mobilise them, that this would include how they’re participating in many different forms, including turning out to vote,” she said.