Nikki Haley argues her supporters won't vote for former President Donald Trump if he becomes the GOP presidential nominee -- pointing to his past comment that her backers will be "permanently barred" from the MAGA movement he started.
"That is an equation to lose a general election," Haley said on Fox News in February. "This is supposed to be a big tent where we want more people to come in."
MORE: Nikki Haley to end presidential campaign, as last major Trump rival exits GOP race: SourcesIt's an example of one of Haley's most notable attacks on her 2024 Republican rival: that he can't unite the party to defeat President Joe Biden. Haley cites how she is getting upwards of 40% of the vote in some nominating contests, though Trump continues to beat her by double digits in all by two of the races so far (in Washington, D.C., and Vermont).
What's more, exit polling indicates many Haley voters in some parts of the country are motivated to vote against Trump: 40% said that's what drove their ballot in South Carolina, her home state, for example.
And in preliminary exit polling from Super Tuesday, 78% of Haley voters in the North Carolina Republican presidential primary, 69% in California and 68% in Virginia said they were unwilling to voice support the party's nominee whoever it is, mirroring Haley's recent hedge on the issue.
"In state after state, there remains a large block of Republican primary voters who are expressing deep concerns about Donald Trump. That is not the unity our party needs for success," Haley spokesperson Olivia Perez-Cubas said in the statement on Super Tuesday, in part.
Now that she announced she's suspending her campaign Wednesday -- where will her anti-Trump voters go?
History shows that many Republicans will likely rally back to Trump in the general, however messy the primary was.
But as President Joe Biden gears up for a likely rematch with Trump, his campaign believes there are opportunities in that apparent weakness, particularly in the suburbs in battleground states, where Trump also suffered losses in 2020.
"Donald Trump's primary performances present a major warning sign for the GOP. He is weak with the voters who are going to decide this election, while these elections show an opportunity for President Biden to expand his coalition," campaign spokesperson James Singer said in a statement.
Singer also contended that general election voters "overwhelmingly" reject policies at the center of some conservative proposals, like those to curtail abortion access and scrap the Affordable Care Act, known as Obamacare, which Trump has insisted he could replace with something better.
"Most importantly, voters want a President who cares about them and their families - and Donald Trump only cares about himself," Singer added, echoing a familiar trail attack line on Trump, who has fired back at Biden over the White House's handling of high inflation and immigration as well as foreign policy.
In the battleground state of North Carolina, one of the states voting in Super Tuesday, Mary Coggins, who identifies as a moderate Republican and said she voted for Trump in 2020, attended Haley's rally on Friday in Charlotte with her young daughter.
Coggins told ABC News she's looking for a president who can be a role model for her daughter and other children -- and she doesn't see Trump fulfilling that role.
She said that if the 2024 race does become another rematch between Trump and Biden, she would consider voting for Biden even though the decision would be hard.
"We think about it a lot," Coggins said. "I mean, some days, most days we lean towards voting for Biden just because we're kind of scared of what things would look like under Trump again, which is tough because we voted for Trump before. But it's hard to say."
In Michigan, considered a must-win for both parties in November, more than 350,000 Republicans voted against the former president in last month's primary and Haley attracted a relatively large chunk of votes from suburban areas outside of Detroit and Grand Rapids.
In South Carolina, where Trump won by 20 points, he also lost three population-rich counties to Haley by double digits.
Candace Reese, a 67-year-old independent voter from Summerville, South Carolina, just outside of Charleston where Haley won, told ABC News that "as much as I think they're both too old, I can't do Donald Trump for another four years."
Jane Miller from Camden, South Carolina, who, like Reese, voted for Haley, said she found Trump scary.
"I think he's a loose cannon and he really scares me. As bad as Biden is, at least we know where he's going," Miller said.
Haley herself has stressed the number of Republicans voting against the former president.
"I know 40% is not 50 percent. But I also know 40% is not some tiny group," she said on primary night in South Carolina, when she vowed to stay in the race until Super Tuesday.
One area where she's winning these voters over, exit polls show, is abortion -- which Democrats see as a key issue in November and a winning one for their side. Abortion access has been on the ballot in seven states since the U.S. Supreme Court decision reversing Roe v. Wade and anti-abortion rights advocates have lost every time, in red and blue states alike.
But there are still many supporters of Haley's who are expected to back Trump if he becomes the nominee, with some saying they still side with the former president and others saying they won't vote for a Democrat in the general election.
Michael Willette, a Republican who planned to vote for Haley in the Maine primary on Tuesday, told ABC News that if Trump were to become the GOP nominee, he would vote for Trump to support the Republican Party. Willette does not agree with many of Trump's past actions but would put that aside to support the GOP in the general election, he said.
"What choice do I have?" Willette said when discussing the possibility of voting for Trump. "I can't vote for Biden. I'm a strong Republican. So I have no choice but to vote for Donald Trump."
But some say that Trump could feel the impact of isolating Haley voters -- just when he needs them.
Doug Heye, a GOP strategist and former communication director of the Republican National Committee, attended Haley's rally in Raleigh, North Carolina, on Saturday. He told ABC News that Trump could have a big problem getting her voters on his side in November.
"What struck me is that what was in that room is precisely what the GOP should be worried about," Heye said. "Rooms full of people, where at the end of the day, if Trump's the nominee, he'll get some of those voters -- there's no doubt about it -- but he will lose a lot. And some of those are independents but a lot of those are Republicans."
Still, Heye stressed that although the Biden campaign should welcome the news about the possibility of picking up supporters from Haley, "they've got their own problem," he said, pointing to the president's weak approval rating and anger from some in his base over the Israel-Hamas war.
"On issue after issue, Trump is beating Biden in the polls, specifically on issues," Heye said, "and so it makes some of this calculus harder."
ABC News' Nicholas Kerr contributed to this report.