Republican US presidential candidate Nikki Haley speaks at a campaign event in Forth Worth, Texas, Monday, March 4, 2024. AP
Haley, 52, the former US ambassador to the United Nations under then-President Donald Trump, was about to suspend her campaign, the Wall Street Journal and CNN reported. She was due to speak in Charleston, South Carolina, at 10:00 am (1500 GMT).
Former president Trump swept 14 out of 15 states up for grabs on the biggest day of the 2024 race so far, with Haley denying him only in the northeastern state of Vermont as he covets a second term in the Oval Office.
Haley, a former South Carolina governor, has failed to throw significant obstacles in Trump's path to the nomination since finishing a distant third in the opening contest in Iowa in January.
Impeached twice, beaten by seven million votes in 2020 and facing 91 felony charges in four trials, Trump has a profile unlike any US presidential election candidate in history.
Yet his appeal among working-class, rural and white voters, particularly on issues like immigration and the economy, has propelled him toward the nomination in one of the most lopsided primary seasons ever seen.
Haley -- a favorite of affluent, suburban voters and university graduates -- was set to collect only a handful of the delegates needed to secure the nomination.
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