Nikki Haley has suspended her presidential campaign after being defeated across the country on Super Tuesday, leaving Donald Trump as the last remaining major candidate for the 2024 Republican nomination.

Ms Haley did not 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.”

Ms Haley, a former South Carolina governor and UN ambassador, was Mr 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 party against embracing Mr Trump, whom she argued was too consumed by chaos and personal grievance to defeat President Joe Biden in the general election.

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

Ms Haley’s defeat marks a painful, if predictable, blow to those voters, donors and Republican Party officials who opposed Mr 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 is unclear whether Mr Trump, who recently declared that Haley donors would be permanently banned from his movement, can ultimately unify a deeply divided party.

Mr Trump on Tuesday night declared that the Republican party was united behind him, but in a statement shortly afterward, Ms Haley’s 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,” Ms 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.”

Ms Haley has made clear she does not want to serve as Mr 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.

Swiftly following her speech on Wednesday, Mr Trump’s campaign in a fundraising email falsely claimed that Ms Haley had endorsed his candidacy.

Earlier this week, Ms Haley said she no longer feels bound by a pledge that required all Republican contenders to support the party’s eventual nominee in order to participate in the primary debates.

On Wednesday, Mr Biden welcomed any voters who had backed Ms Haley, acknowledging Mr 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,” Mr 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.”

Ms Haley leaves the 2024 presidential contest having made history as the first woman to win a Republican primary contest. She beat Mr 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 but was unable to knock Mr Trump off his path to a third straight nomination.

However, Ms Haley’s allies noted that she exceeded most of the political world’s expectations by making it as far as she did.