Nikki Haley has one last card to play: will she eventually endorse Trump?

Nikki Haley’s withdrawal from the Republican presidential primary on Wednesday was “not a shocker”, a leading anti-Trump conservative said, in a contender for understatement of the political year.

“As we’ve said for months,” Tara Setmayer added, “she has no path and [Donald] Trump will be the GOP nominee.”

But Setmayer also pointed to the impact Haley did make in the Republican primary, what it means for Trump, and the choice now facing the former South Carolina governor and UN ambassador as she seeks to retain political relevance.

“Now let the over/under begin for when Haley endorses Trump,” Setmayer, a Republican operative turned member of the anti-Trump Lincoln project, said on social media.

On Super Tuesday, Haley added Vermont to her weekend win in Washington DC but otherwise suffered a wipeout. Though Trump has not yet mathematically secured the nomination, Haley bowed to the inevitable the following morning.

There was consolation for Haley. Across the slate of states which voted on Tuesday, she once again finished closer to Trump than expected, her vote shares above those predicted by polling.

Tellingly, that illustrated sizable opposition to Trump among some Republicans and conservative independents.

“Nikki Haley’s performance across the board is a warning signal for … Trump’s lieutenants,” Rick Wilson, a Republican strategist and ad maker turned Lincoln Project co-founder, wrote on Substack.

“Trump’s senior strategist, Chris LaCivita, saw the results in key states late last night, read the exit poll data, scanned the turnout areas, and knew within hours that Trump’s party isn’t unified.

“It’s smaller, darker, and more passionately devoted to the dear leader, but depending on the state, between 25% and 40% of Republican and conservative independents just aren’t into Donald Trump.”

If most of those voters do not come back, Trump will face a near-impossible task in November against Joe Biden.

The question for Trump and his aides, therefore, is how to get Haley onside and win back as many of her supporters as possible, as quickly as possible, while keeping them out of Biden’s camp.

Whether Haley will endorse Trump, it follows, is now a central campaign question.

In Charleston on Wednesday, announcing her withdrawal, Haley said that in campaigning against Trump for so long, with so little chance of success, she had “wanted Americans to have their voices heard”.

“I have done that,” she said. “I have no regrets.”

But having recently avoided recommitting to supporting the Republican nominee – which she previously pledged to do – she did not go on to endorse him.

Having ruled out a third-party bid, an endorsement is Haley’s last card to play. Endorsements are often bartered for plum jobs (if not in this case vice-president, which Haley has said she does not want). Endorsements, and campaign-trail efforts on behalf of the nominee, can also be used to win support for candidacies yet to come, in Haley’s case after Trump finally leaves the stage.

It is fair to say Haley has earned her position of relative influence in a party controlled by Trump. A rare Republican woman of colour in a primary dominated by white men, she vastly outperformed expectations.

Though she started out with single-figure polling numbers, confident debate-stage displays saw her eclipse rivals including the former vicepresident Mike Pence and Ron DeSantis, the hardline Florida governor who was initially expected to be Trump’s leading challenger, perhaps even his conqueror.

Trump skipped every debate. Tellingly, though, he did not need to be onstage to dominate his opponents who were. Before the field began to shrink, all candidates other than Chris Christie and Asa Hutchinson, two doomed anti-Trumpers, fought shy of attacking him, aware of his grip on the base.

When DeSantis quit, before the New Hampshire primary, Haley finally had a clear field to take the fight to Trump. She began to turn fire his way. But however strongly she spoke – calling the 77-year-old former president “unhinged” and diminished”, doubting he would adhere to the constitution – it was clearly too little, too late.

Haley has disappointed Trump’s opponents too.

She has said she will vote for Trump over Joe Biden. She also said that if she was elected, and if Trump was convicted on any of the 91 criminal charges he faces, she would give him a pardon.

Though Haley has “earned the votes and support of millions of Republican and conservative independent voters in her brief time in the spotlight”, Wilson said, she will soon “break their hearts for nothing.

“Reality has now set in for millions of Republican voters. They must choose between Donald Trump and Joe Biden. In all likelihood, Nikki Haley will make the wrong choice and back Trump.”

That endorsement, Wilson said, “will prove it was all for nothing. The abyss is calling, and she’s peering down into the darkness.”