A dog sits with an "I Voted" sticker after their owner voted at a polling location during the "Super Tuesday" presidential primary in Los Angeles, California on March 5, 2024
A dog sits with an "I Voted" sticker after their owner voted at a polling location during the "Super Tuesday" presidential primary in Los Angeles, California on March 5, 2024 AFP News

Polls began closing Tuesday on the biggest day of the year for US presidential primaries, with Donald Trump expected to cement his hold on the Republican nomination and set up a rematch with President Joe Biden in November.

"Super Tuesday" decides Republican and Democratic primaries in the giant states of California and Texas, as well as more than a dozen other battlegrounds, and can make or break would-be presidents' White House ambitions.

But this year's contest has been sapped of much of its suspense as Biden and Trump have all but locked up their parties' nominations.

Trump's longshot challenger, former UN ambassador Nikki Haley, has failed to provide a significant obstacle in Trump's path to the nomination, losing every state that has so far held votes.

Trump scored early victories Tuesday, notching a win in Virginia, which was thought to be one of Haley's best opportunities for success, and North Carolina.

Impeached twice, beaten by seven million votes in 2020 and facing 91 felony charges in four jurisdictions, Trump has a profile unlike any US presidential election candidate in history.

Yet his appeal among working-class, rural and white voters is expected to carry him to the threshold of the nomination, with victories in most of the 15 battlegrounds on offer Tuesday -- if not a clean sweep.

Polling averages from RealClearPolitics show 77-year-old Trump 65 points clear in the primary, and two points ahead of Biden in a hypothetical one-on-one match-up.

Barring massive upsets, Haley looks set to collect only a handful of the delegates needed to secure the nomination with her narrow support base of affluent, suburban university graduates.

"Today's her last day," physicist Andrew Pugel told AFP at a polling station in Huntington Beach, California, though he added that it would be smart of Trump to make her his running mate and "unite the country."

Maps of the US showing by month the states and territories that will vote during the primaries and caucuses to choose a presidential nominee for the Democratic and Republican parties.
Maps of the US showing by month the states and territories that will vote during the primaries and caucuses to choose a presidential nominee for the Democratic and Republican parties. AFP News

The expected Trump surge comes a day after the Supreme Court denied a bid by a handful of states to keep him off the ballot over his push to overturn the 2020 election, when he refused to concede defeat to Biden and riled up a mob that assaulted the US Capitol.

The states up for grabs Tuesday offer 70 percent of the delegates Republicans need to be named the party's standard-bearer at the summer convention.

Trump would not be able mathematically to close out the contest but he expects to be anointed by March 19 at the latest, according to his campaign.

Biden, 81, is on the ballot in the Democratic primaries, but faces little threat from two long-shot challengers, making his re-nomination a formality.

He is due to deliver the annual State of the Union address to Congress on Thursday, and will be keen for strong showing ahead of the high-profile opportunity to lay out his campaign platform and attack Trump.

With some forecasts of a low turnout Tuesday, pop star Taylor Swift urged people to vote in an Instagram message. She did not endorse any candidate, though Democrats hope she will publicly back Biden in November.

Trump said over the weekend that his campaign was moving "like a rocket" towards the Republican nomination and made clear he is looking past the primary to Election Day.

However, Haley's campaign questions whether middle-of-the-road Republicans will drift away from Trump.

Some primary-watchers expect Haley, 52, to end her campaign after Super Tuesday, although she could see victories in a couple of states as a mandate to carry on.

She also warns of the "chaos" surrounding a candidate who in just the last few months has been labeled an insurrectionist by a federal judge, and ordered to pay hundreds of millions of dollars in his civil cases.

The ex-president has spent nine days in court this year alone, and complains his prosecutions are keeping him from the campaign trail -- although he has turned court appearances into part of his fundraising campaign.

Stephanie Perini-Hegarty voted for Biden in Quincy, Massachusetts.

"I think we need a leader who is not involved in any corruption, and who is going to look out for the best interests of the people. And I think that the Democrats right now are the people that do that," the 55-year-old told AFP.

The states up for grabs Tuesday, which include the giant battlegrounds of California and Texas, offer 70 percent of the delegates a candidate needs to be named the presumptive Republican nominee
The states up for grabs Tuesday, which include the giant battlegrounds of California and Texas, offer 70 percent of the delegates a candidate needs to be named the presumptive Republican nominee AFP News
Donald Trump