When Ronald Reagan campaigned at South Carolina's statehouse in 1980, some 10,000 enraptured supporters showed up for a man who would become an icon of conservatism unrivaled in modern US history.

Donald Trump -- who spoke at the same building Saturday as he attempts to reboot his faltering bid for another four years in the White House -- might lack Reagan's everyman appeal, but his admirers are every bit as ardent.

"He has incredible charisma. He was one of the greatest presidents in the modern era -- up there with Reagan and JFK," said Ronald Soloman, who had traveled from his home near the 76-year-old Republican's Palm Beach estate in Florida to sell Trump hats and other merchandise.

The Justice Department made up "the whole Russian collusion hoax, it was all a bunch of nonsense," said Soloman, echoing numerous supporters who made clear that, in their eyes, the 45th president can do no wrong.

The rally in the South Carolina capital of Columbia -- his first since his launch in November -- marked Trump's biggest test yet as he bids to recapture the energy that swept him to the presidency seven years ago.

But aides have reportedly been fretting about his ability to draw the crowds he was able to assemble in 2016, and the rally was a much smaller affair than Reagan's speech more than 40 years ago, with a few hundred attendees.

Trump has also been buffeted by legal woes, as he is investigated for suspected financial fraud, election interference and his role in the 2021 assault on the US Capitol.

- 'Solid base' -

New polling from the conservative South Carolina Policy Council shows voters in the Palmetto State are no longer sold on the former president.

In a survey of likely 2024 Republican primary voters, just 37 percent said the party should nominate Trump in 2024, while 54 percent agreed that "the country would be better off" without him.

Political analysts say Trump's reputation has been damaged by a dinner he hosted with a notorious anti-Semite, a call in December to suspend the Constitution and the continuing fallout from the 2021 assault on the US Capitol by his supporters, and the Republicans' poor midterm performance.

Meanwhile, there is a burgeoning taste for a potential presidential bid by Florida Governor Ron DeSantis, who has growing support among Trump's evangelical support base.

"DeSantis is an unbelievably great candidate. But I don't think that DeSantis will be able to win a primary against Trump," Soloman told AFP.

"I believe that Trump has a solid base of 35 to 40 percent. And with a large field, which there will be, that means the field against him will be divided and nobody will be able to overtake him."

Trump was more than an hour late for his Columbia rally after being held up at an earlier event in New Hampshire, giving fans more time to swap their favorite anecdotes outside the statehouse.

- Delivering on promises? -

In the speech, Trump touted his record in delivering on campaign promises: building a border wall, which largely didn't happen; restoring the US military, a claim which is difficult to pin down; and eroding Americans' right to abortion, which was resoundingly accomplished.

Aminu Rufai, 40, originally from Ghana, called Trump "a man of his word."

"He's the one that can take care of this economy, he's the one that can tackle our immigration problems, our social problems like abortion," he said.

So was Rufai disheartened when Trump failed to deliver on building a "big beautiful wall" to keep out migrants at the southern border?

"I'm not frustrated but I wish he would come back and finish it off, to protect our borders," Rufai told AFP.

Jeff Fitzharris, 52, an entrepreneur who has a business in nearby Charleston selling bottles of "Make Honey Great Again," described Trump as "a great guy, a great businessman."

"The other thing is that no one's paying him... Literally every politician that we have in this country is being given paychecks to represent people through lobbyists and Trump is self-funded," he told AFP.

"He really doesn't owe anybody anything. And let's be honest -- he could go to Florida and live a nice life. Or he could save our country, and that's what he's going to do."