Donald Trump will find out in a month whether he has an overwhelming lead for the Republican presidential nomination or if his opponents can pull off an upset when the 2024 US primary season begins in the Midwestern state of Iowa.

Trump is facing four pending criminal indictments, which could result in his imprisonment.

Nevertheless, at this stage of the campaign, he has one of the largest poll advantages over Republican opponents in modern history.

As the party looks to unseat Democratic President Joe Biden, several Republicans are vying to run in the November election next year, but so far Trump is leading the field.

"We're going to make America great again," Trump promises at his rallies, echoing the slogan that catapulted him to office in 2016.

However, polls this far ahead of the vote should be regarded cautiously, as previous US elections have demonstrated.

The true test will come in the intraparty nomination races in several states, beginning on 15 January with the Iowa caucus, where voters will hear from Trump for the first time since he left the White House.

Iowa's voters will kick off the primary season as they have every year since 1972, assembling in locations such as fire stations and school gyms to cast ballots at individual precinct meetings, or caucuses, as tradition demands.

Haley, DeSantis vie

In Iowa as elsewhere, Trump still has a loyal base that brushes aside his legal troubles.

"I don't even understand what the crime is," said Adam Miller, a 61-year-old farmer and Trump supporter whom AFP met in Makoqueta, a town in eastern Iowa near the Mississippi River.

"I mean, if he's accused of murder or bribery… then that would change my mind," he said.

On 15 January at 7 p.m., this dark-haired, bespectacled man will gather with residents of his community, a three-hour drive from Chicago, to fill out a ballot with the name of the billionaire, who is accused of, among other things, election interference and mishandling classified information.

On that night, six other Republicans will be in the running to block Trump's path. Only two still seem to have a chance.

They include Florida Governor Ron DeSantis, a conservative with hard-right positions on immigration and LGBT+ rights who has staked everything on Iowa, crisscrossing the state's 99 counties in the space of a few months.

Falling star

The 45-year-old  DeSantis can also count on the patronage of Iowa Governor Kim Reynolds, who has endorsed him. While Reynolds remains popular among Republicans, Trump savaged her after she backed DeSantis, branding her "America's most unpopular governor."

Support for DeSantis, a former naval officer, appears to have plummeted in recent months, which some blame on his occasional wooden demeanor and lack of charisma.

Then there's former UN ambassador Nikki Haley, the new darling of the American right.

The 51-year-old former governor of South Carolina has cut a different path with a more moderate stance on reproductive rights, aware that her party has suffered several electoral setbacks since the Supreme Court last year overturned the constitutional right to abortion.

Throughout the campaign, both Haley and DeSantis have employed fancy footwork to avoid direct attacks on Trump for fear of offending his supporters.

Both hover around 12 percent in the polls, a far cry from the former president's 60 percent.

But observers are not ruling out the possibility either of them could spring a surprise and nibble away at the tempestuous Republican's dizzying lead.

"A huge victory means that Trump will look more vulnerable in the GOP nominating contest than observers, donors, and voters expected," Brown University political scientist Wendy Schiller told AFP.

Slim chance

After Iowa, the electoral spotlight turns to New Hampshire, on the border with Canada, then to the casino state of Nevada and South Carolina at the end of February.

By June, all 50 states will allocate their delegate quotas to candidates for July's Republican National Convention, which will nominate the party's flag bearer for the election.

On the Democratic side, barring a huge surprise, incumbent Biden, 81, will be nominated in August at the party's convention in Chicago. This will occur despite repeated criticism about his age.

Two candidates, congressman Dean Phillips and best-selling author Marianne Williamson, are challenging Biden for the Democratic nomination, but their chances are slim.                 

With AFP