Donald Trump
SCOTUS hears arguments on whether Donald Trump is immune from prosecution after leaving office for "official acts" while he was president. AFP

Donald Trump faced Republican voters for the first time as a convicted felon on Tuesday during the final state primaries for the 2024 presidential nomination, where he continued to sweep up votes.

The ex-president has already locked up the Republican nomination to run against President Joe Biden, making the votes in Montana, New Jersey, New Mexico and South Dakota formalities.

However, some political observers had wondered if Republican voters might sour on Trump's divisive candidacy after he was found guilty last week of falsifying business records in a conspiracy to unlawfully influence the 2016 election.

Though Trump steamrolled over other Republican presidential hopefuls, he faced a hiccup at a guaranteed-win primary earlier this year.

In May, two months after the last Republican rival standing, Nikki Haley, abandoned her campaign, she still won nearly 22 percent of the votes in the Indiana primary.

Trump on Tuesday picked up 85 percent of the vote in New Mexico, with Haley picking up nine percent after more than 95 percent of ballots were in.

In Montana, where Haley was not on the ballot, Trump picked up nearly 91 percent, while nine percent selected no preference, with 83 percent of the votes in.

The ex-president was uncontested in New Jersey and South Dakota.

It's unclear if support for Haley among a minority of Republicans could translate into trouble for Trump in November's general election, or if those voters -- faced with the choice between Trump and Biden -- will come home to the ex-president's camp when the money is truly on the line.

Haley also picked up a fifth of Maryland's Republican primary voters, as well as 18.2 percent of the vote in Nebraska and 9.4 percent in West Virginia, all after she ended her campaign.

Haley, a former ambassador to the United Nations, has said she would vote for Trump.

Trump claims that the historic verdict has only made him stronger, and his campaign has seen eye-watering levels of donations fueled by the trial.

A jury returned guilty verdicts against Trump on Thursday for all 34 charges of falsifying business records to cover up a sex scandal and cheat voters in the final stages of his winning 2016 campaign against Hillary Clinton.

Prosecutors said Trump had sex with porn actress Stormy Daniels soon after his wife Melania had given birth in 2006, and then paid hush money a decade later to avoid the fallout, before creating false paperwork to conceal the payment.

He is due for sentencing on July 11 -- just days before the Republican National Convention in Milwaukee, where he will be officially anointed as the nominee.

Trump faces three other criminal cases, including charges related to his unprecedented attempts to overturn his 2020 election loss to Biden.

Republican donors appear to have rallied behind their standard-bearer.

The Florida billionaire's campaign said Friday it had raised a staggering $53 million in online small-dollar donations in the hours after the verdict was announced -- more than a third from new donors.

But a tenth of registered Republican voters said Trump's conviction for falsifying business records would make them less likely to support him for president, in an Ipsos poll that closed on Friday.

In a tight race against Biden, even a small loss of support in his base could hurt Trump significantly.