NEW YORK (AP) — Nikki Haley suspended her presidential campaign on Wednesday after being soundly defeated across the country on Super Tuesday, leaving Donald Trump as the last remaining major candidate for the 2024 Republican nomination.

Haley didn't endorse the former president in a speech in Charleston, South Carolina. Instead, she challenged him to win the support of the moderate Republicans and independent voters who supported her.

"It is now up to Donald Trump to earn the votes of those in our party and beyond it who did not support him. And I hope he does that," she said. "At its best, politics is about bringing people into your cause, not turning them away. And our conservative cause badly needs more people."

Haley, a former South Carolina governor and U.N. ambassador, was Trump's first significant rival when she jumped into the race in February 2023. She spent the final phase of her campaign aggressively warning the GOP against embracing Trump, whom she argued was too consumed by chaos and personal grievance to defeat President Joe Biden in the general election.

Her departure clears Trump to focus solely on his likely rematch in November with Biden. The former president is on track to reach the necessary 1,215 delegates to clinch the Republican nomination later this month.

Haley's defeat marks a painful, if predictable, blow to those voters, donors and Republican Party officials who opposed Trump and his fiery brand of "Make America Great Again" politics. She was especially popular among moderates and college-educated voters, constituencies that will likely play a pivotal role in the general election. It's unclear whether Trump, who recently declared that Haley donors would be permanently banned from his movement, can ultimately unify a deeply divided party.

Trump on Tuesday night declared that the GOP was united behind him, but in a statement shortly afterward, Haley spokesperson Olivia Perez-Cubas said, "Unity is not achieved by simply claiming, 'We're united.'"

"Today, in state after state, there remains a large block of Republican primary voters who are expressing deep concerns about Donald Trump," Perez-Cubas said. "That is not the unity our party needs for success. Addressing those voters' concerns will make the Republican Party and America better."

Haley has made clear she doesn't want to serve as Trump's vice president or run on a third-party ticket arranged by the group No Labels. She leaves the race with an elevated national profile that could help her in a future presidential run.

Trump, in a social media post, continued to mock her, while at the same time extending an invitation to "all of the Haley supporters to join the greatest movement in the history of our Nation. BIDEN IS THE ENEMY, HE IS DESTROYING OUR COUNTRY," he wrote. "MAKE AMERICA GREAT AGAIN!!!"

On Wednesday, Biden welcomed any voters who had backed Haley, acknowledging Trump's previous rejection of her supporters.

"Donald Trump made it clear he doesn't want Nikki Haley's supporters. I want to be clear: There is a place for them in my campaign," Biden said in a statement. "I know there is a lot we won't agree on. But on the fundamental issues of preserving American democracy, on standing up for the rule of law, on treating each other with decency and dignity and respect, on preserving NATO and standing up to America's adversaries, I hope and believe we can find common ground."

By staying in the campaign until now, Haley drew enough support from suburbanites and college-educated voters to highlight Trump's apparent weaknesses with those groups.

In AP VoteCast surveys conducted among Republican primary and caucus voters in Iowa, New Hampshire and South Carolina, between 61% and 76% of Haley's supporters said they would be so dissatisfied if Trump became the GOP nominee that they wouldn't vote for him in the November general election. Voters in the early Republican head-to-head contests who said they wouldn't vote for Trump in the fall represented a small but significant segment of the electorate: 2 in 10 Iowa voters, one-third of New Hampshire voters, and one-quarter of South Carolina voters.

Haley leaves the 2024 presidential contest having made history as the first woman to win a Republican primary contest. She beat Trump in the District of Columbia on Sunday and in Vermont on Tuesday.

She had insisted she would stay in the race through Super Tuesday and crossed the country campaigning in states holding Republican contests. Ultimately, she was unable to knock Trump off his glide path to a third straight nomination.

Haley's allies note that she exceeded most of the political world's expectations by making it as far as she did.

She had initially ruled out running against Trump in 2024. But she changed her mind and ended up launching her bid three months after he did, citing among other things the country's economic troubles and the need for "generational change." Haley, 52, later called for competency tests for politicians over the age of 75 — a knock on both Trump, who is 77, and Biden, who is 81.

Her candidacy was slow to attract donors and support, but she ultimately outlasted all of her other GOP rivals, including Florida Gov. Ron DeSantis, former Vice President Mike Pence and Sen. Tim Scott, her fellow South Carolinian whom she appointed to the Senate in 2012. And the money flowed in until the very end. Her campaign said it raised more than $12 million in February alone.

She gained popularity with many Republican donors, independent voters and the "Never Trump" crowd, even though she criticized the criminal cases against him as politically motivated and pledged that, if president, she would pardon him if he were convicted in federal court.

___

Kinnard reported from Washington. Meg Kinnard can be reached at http://twitter.com/MegKinnardAP, and Steve Peoples can be reached at http://twitter.com/sppeoples.