Donald Trump eyes Super Tuesday sweep as rival Nikki Haley vows to fight on

Donald Trump aims to deliver a Super Tuesday knockout blow to his lone challenger for the Republican US presidential nomination, Nikki Haley, as 15 states hold Republican contests on the biggest voting day of the primary season.

The former president, who has dominated the Republican campaign from the start despite his litany of criminal charges, has swept all but one of the contests so far, winnowing a sprawling Republican field of candidates down to two.

While Trump cannot win enough delegates on Tuesday to formally clinch the nomination, another dominant performance would further pressure his remaining rival. Tuesday’s contests will award more than one-third of Republican delegates - and more than 70 per cent of the number needed to secure the nomination.

A third consecutive nomination for Trump would set up a rematch with Democratic President Joe Biden in November’s election. Biden is expected to win Tuesday’s Democratic contests easily, though activists opposed to Biden’s Israel policy are calling on Muslim Americans and progressives to vote “uncommitted” in Minnesota in protest.

Haley, a former United Nations ambassador under Trump, has faced mounting questions about how long she will continue her long-shot campaign, particularly after losing her home state of South Carolina 10 days ago.

Her campaign did not schedule any public events on Super Tuesday or beyond.

“As much as everybody wants to go and push me out, I’m not ready to get out yet,” she told Fox News in an interview.

Trump was leading Haley in every Super Tuesday state where public polling data was available, according to poll tracking website 538. In California and Texas, which together account for more than 300 delegates, Trump was ahead by an average of more than 50 per cent.

But Haley allies see a narrow window of opportunity to win states such as Virginia, Massachusetts and Vermont, which have more of the wealthy, college-educated voters who tend to support her candidacy.

Those three states are also among several on Super Tuesday that do not require primary voters be registered Republicans. Independent and moderate voters have favoured Haley over Trump in early voting states, according to exit polls from Edison Research.

Asked if he would reach out to Haley after Tuesday’s results, Trump said his focus was on Biden.

“I think we’re going to win every state tonight,” he told Fox News in a separate interview.

While Trump will stage an event on Tuesday night at his Florida resort, Biden has no separate campaign events planned.

Voters were also casting ballots in down-ticket races, including two key contests in California to identify potential successors to the late Democrat Dianne Feinstein in the Senate and recently deposed Republican Speaker Kevin McCarthy in the House of Representatives.

Trump’s advisers have said they expect him to eliminate Haley mathematically no later than March 19, when two-thirds of the states will have voted. Trump is scheduled to begin his first criminal trial six days later in New York, where he is charged with falsifying business records to conceal hush money payments to a porn star during his 2016 presidential run.

Haley scored her first victory on Sunday in Washington, DC, becoming the first woman ever to win a Republican presidential primary.

While Haley has failed to slow Trump’s momentum, her challenge has highlighted some of his potential vulnerabilities in a general election. She has repeatedly noted that she reached 40 per cent in some state contests, arguing that her performance shows independents and moderate Republicans harbour unease about a second Trump term.

Trump faces both federal and state charges for election interference, though it is unclear whether either case will reach trial before November’s election. He also faces federal charges for retaining classified documents after leaving office, as well as this month’s hush-money trial.

Trump has pleaded not guilty in every case and claimed without evidence that they are part of a Democratic conspiracy to prevent him from returning to power, leveraging his legal troubles to raise money and maintain supporters.

The US Supreme Court on Monday ruled that states cannot remove Trump from their ballots based on a US constitutional amendment barring insurrectionists from holding office.