Trump weakening? Not judging by his Iowa swing.

Braving the cold March Iowa wind, Patty Havill stands amid a snaking line of red MAGA hats and flag-themed costumes, waiting to see the one man she believes can still save America from all its problems. Other Republican presidential hopefuls have been through town recently – including, on Friday, hot-ticket Florida Gov. Ron DeSantis – but Ms. Havill is single-minded in her devotion. For her, it’s Donald Trump or no one.

“Our country is in chaos. We need him to straighten it out,” says the retired nurse. “Trump is the only one.”

Since launching his third bid for the White House some four months ago, Donald Trump’s campaign has, from the outside, frequently seemed fizzling and unfocused. The former president is juggling distractions in the form of mounting legal troubles and the very real possibility of a criminal indictment. After many of his hand-picked candidates lost in the 2022 midterms, his grip on the GOP was widely proclaimed to be weakening – with even his former vice president apparently gearing up to take him on.

But those factors belie a set of strengths that are in many ways now becoming evident.  

As the contours of the 2024 primary battle start to come into focus, Mr. Trump is already benefitting from some of the same circumstances that helped him in 2016. A large, unwieldy Republican field that divides the anti-Trump vote. Opponents too afraid to attack him directly. Above all, a set of diehard fans like Ms. Havill, who are providing him with a solid, unshakeable floor of support.

At the same time, it’s becoming clear Mr. Trump is bringing an entirely different level of political and professional experience to this primary process than in 2016. He’s wooing key officials for endorsements and behind-the-scenes support. And he’s wasting no time building an on-the-ground apparatus with experienced hands in early voting states like Iowa that could give him a significant edge over his GOP rivals – some of whom, like Governor DeSantis, have not even formally entered the race.

“You’d be foolish to underestimate Donald Trump,” says Luke Martz, a Republican strategist based in Iowa. 

Some Trump supporters began lining up more than 10 hours in advance of Monday’s event in Davenport, a city in eastern Iowa on the Mississippi River, where Illinois-born Ronald Reagan began his career as a radio sportscaster in the 1930s.

“This isn’t a rally. We’ll be back for a rally soon,” Mr. Trump said, midway through his two-hour speech at a packed theater, in his first visit to the state where the 2024 road to the White House begins for Republicans. As he spoke, volunteers collected names, emails, and addresses from the audience and passed out voter registration forms. 

“I said, ‘Why aren’t we doing one at an airport where we can have 50,000 people?’ They said, ‘Sir, it’s too cold.’ That was a good call,” he said, cracking a smile. “Because it’s very cold outside.” 

Earlier, Mr. Trump made a brief unannounced stop at a local restaurant where he posed for photos with diners, the kind of retail politicking that Iowans have come to expect. At the theater, he took questions at the end from the audience after joking that the evening should end on a high note, like a concert that ends with a great encore. 

In 2016, Mr. Trump famously finished second in the Iowa caucuses behind Texas Sen. Ted Cruz, after a campaign that relied on celebrity and media exposure but fell short on organization. (Mr. Trump conceded but then claimed Senator Cruz “stole” the election.) This time, the former president seems determined not to make the same mistake. Mr. Trump has hired Marshall Moreau, who helped GOP candidate Brenna Bird defeat a 10-term Democratic attorney general in November, to lead his Iowa efforts. 

Other hires include state lawmaker Bobby Kaufmann, who appeared on stage with the former president in Davenport. His father, Jeff Kaufmann, a Trump ally, is the chairman of the Iowa Republican Party, leading some Republicans to grumble about a potential conflict of interest in a party-run caucus. 

Also on Team Trump: Eric Branstad, whose father Terry Branstad is a popular former Iowa governor who served as Mr. Trump’s ambassador to China. Eric Branstad helped run Mr. Trump’s state campaigns in 2016 and 2020 and is a senior advisor this time. 

“Having a strong organizational base in Iowa is really important,” says Doug Gross, a Republican activist here who has been critical of the former president. To win here, campaigns need to be able to convert pledges of support into actual votes on the one night in January – typically a dark, frigid night – that matters.

Mr. Trump’s core of committed supporters, even if they’re a minority, are an enormous asset in a caucus, notes Mr. Gross. “You’ve got to be a pretty committed partisan to go to a caucus and get your voice heard,” he says. “That gives [Mr. Trump] a natural advantage.” But having a campaign that understands the complicated mechanics and rules of caucuses, and can maneuver strategically, can compound that advantage dramatically.

Other Republicans note that the pressure will be on Mr. Trump to win – and to win convincingly – in Iowa, unlike in 2016 when his campaign benefitted from low expectations. Indeed, even a narrow Trump win could be seen as a disappointment, giving momentum to a second-place finisher.

 “There’s a big hole for someone to come through,” says David Kochel, an Iowa-based strategist and former advisor to Mitt Romney who helped lead Jeb Bush’s 2016 campaign.

Mr. Trump’s appearance in Iowa came on the heels of a hotly anticipated visit by his putative rival, Governor DeSantis. Mr. DeSantis held two events Friday that were ostensibly to promote his new book but were widely seen as putting down a marker for 2024. He met Republican state lawmakers after his stop in Des Moines, where he was joined by Iowa Gov. Kim Reynolds, who also introduced Mr. Trump at his event. 

While early national polls often reflect little more than name recognition, the upward trajectory for Mr. DeSantis in states like Iowa seems clear. And his rise in popularity is coming at Mr. Trump’s expense, sharpening the rivalry between the two men, and setting the stage for a potentially drawn-out battle. 

An Iowa poll released Friday showed a softening in Mr. Trump’s support, with just 47% of Iowa Republicans saying they would “definitely” vote for him if he’s the GOP nominee, down significantly from 69% in June 2021 (another 27% would “probably” vote for him). The former president’s favorability rating among Iowa Republicans has also declined more than 10 points and is now at 80%, just slightly higher than Mr. DeSantis’ at 75%. (That said, 1 in 5 respondents said they didn’t yet know enough about Mr. DeSantis to assess him.) 

“There’s a subset that will be with President Trump no matter what,” says Brett Barker, GOP chairman in Story County. But “I think Iowans in general have an open mind.” 

At a recent event in Iowa for defeated Arizona gubernatorial candidate Kari Lake, former Gov. Branstad told the Monitor that he would remain neutral in 2024. (In 2016, he warned Iowans not to back Senator Cruz over the Texan’s opposition to ethanol subsidies.) But he expressed doubts about Mr. Trump’s chances this time because, he said, the former president has “too much baggage.” 

Judging by the responses from Mr. Trump’s supporters, social and cultural grievances will drive the race for the GOP nomination in 2024. The biggest and most sustained applause was for Mr. Trump’s calls to ban transgender athletes from women’s sports, stop the teaching of critical race theory in schools, and “break up” the federal Department of Education. 

Mr. Trump seemed to take note. “Look at the hand you get for that,” he said, after the crowd roared its approval. “Bigger than ‘we’re going to be energy independent,’ ” he said, referring to one of his regular applause lines. 

By contrast, Mr. Trump’s digs at Florida’s governor – “Ron DeSanctimonious” – received a more muted response. (Mr. DeSantis has so far resisted making direct attacks on the former president.) He said Mr. DeSantis had voted in Congress to cut farm subsidies, and to reduce Social Security and Medicare benefits, both of which Mr. Trump said he would protect.

The president expounded at length on his administration’s record of fighting trade wars with China, Mexico, and Europe, and standing up for farmers in Iowa, including ethanol producers. “I fought for Iowa ethanol like no president in history,” he said. 

Outside the theater, some attendees said they would support Mr. DeSantis as a presidential candidate, should he win the nomination instead of Mr. Trump. Others suggested the Florida governor, who is 44, ought to wait his turn. 

“I think DeSantis would make a good VP, but Florida needs him right now,” says Roy Nelson, a retiree from Iowa who had traveled from Nevada for the event. “He’s a young man. He has time. This will probably be Trump’s last shot.”