FILE - An audience member listens to Republican presidential candidate Florida Gov. Ron DeSantis speak during a meet and greet, Saturday, Oct. 14, 2023, in Creston, Iowa. (AP Photo/Charlie Neibergall, File)

CORALVILLE, Iowa (AP) — Donald Trump was uncharacteristically serious when he implored an audience in eastern Iowa to carry him to a blowout in next month's Republican caucuses.

“The margin of victory is very important, it's just very important,” Trump told about 1,000 people attending a Wednesday rally aimed at organizing campaign volunteers. “It’s time for the Republican Party to unite, to come together and focus our energy and resources on beating Crooked Joe Biden and taking back our country. Very simple.”

For the blustery former president, it was both caution against complacency and a sign that he and his team believe the first contest on Jan. 15 can be not just the start of the nominating campaign, but the beginning of the end.

Trump is the overwhelming favorite to win Iowa, one month away from the caucuses. A myriad of well-qualified GOP challengers and anti-Trump groups haven't changed that dynamic after crisscrossing the state over the last year and spending more than $70 million in Iowa on advertising, according to the media tracking firm AdImpact. And unlike his first time in the caucuses, which he narrowly lost in 2016, Trump's campaign is now run by Iowa veterans who are not just locking in caucus commitments but building a formidable organization to try to lock in his lead.

Among rival campaigns, most question not whether Trump will win, but by how much — and whether a second-place finisher can claim momentum for the rest of the race.

“For me, it looked like for a long time there was a narrow lane, but there was a lane, for a not-Trump candidate,” said Gentry Collins, a veteran Republican strategist and former state GOP executive director who ran Mitt Romney's 2008 GOP caucus campaign. “But there isn’t really a single alternative people can rally around.”

Trump was the first choice of 51% of likely Iowa caucus participants in a Des Moines Register-NBC News-Mediacom Iowa Poll published Monday. Florida Gov. Ron DeSantis, who has vowed that he will win Iowa, had the support of 19%. Former United Nations Ambassador Nikki Haley, who has suggested she can beat DeSantis in the state and go head to head with Trump in later primaries, was at 16%.

Next year's GOP nomination is officially an open race. But many primary voters believe Trump was cheated in 2020 when he lost his reelection bid to Democrat Joe Biden. Multiple government and outside investigations have not found evidence of any voter fraud, despite Trump's frequent and repeated false claims that are often repeated by many of his supporters.

Trump remains popular with Republicans, both in Iowa and nationally, who credit him for his handling of the economy, the U.S.-Mexico border, and his appointment of three Supreme Court justices who voted to overturn a federally guaranteed right to abortion.

“You’ve got basically a quasi-incumbent president," said Whit Ayres, a Republican pollster and senior adviser to Marco Rubio’s 2016 campaign. “Of course, he's got the overwhelming advantage.”

Beyond Trump's built-in advantages, a massive and ongoing effort on his behalf in Iowa reflects the campaign’s realization — especially compared to his seat-of-the-pants 2016 effort — that turning out many thousands of Iowans to caucus on a cold January night requires intense organizing.

State Republican Party officials who run the contests and strategists with the various campaigns suggest January's caucuses will break the record of nearly 187,000 people in 2016.

Trump's team says it has collected and processed tens of thousands of commitment cards, most of them coming from his 11 visits to Iowa in the past three months. Aides say the cards are entered into a database within three days before a campaign volunteer replies by phone.

Though Trump has visited far less often than DeSantis, Haley and others, he has drawn more than 20,000 to events since early September, thousands of whom say they are first-time caucus participants.

When asked if they were first-timers, hundreds of people raised their hands at Wednesday's event in Coralville. The audience sat before a stage flanked by large video screens with a QR code and text code that guided them to the campaign’s digital portal.

Volunteers circulated around the Hyatt Regency hosting the event, identifiable with their white ball caps emblazoned in gold lettering with “Trump Caucus Captain.”

One volunteer, a University of Iowa student, approached Ginger Marolf as she was waiting in a line of hundreds of people snaking around the hotel. The student asked Marolf to fill out a caucus pledge card and give it back so they could get “an accurate count of how many people support Trump in Iowa.”

After signing her card, Marolf called Trump a fighter for “us, the people” and suggested that she isn’t considering any of the other Republican candidates.

“Trump needs to be back in office, like now,” she said, blaming Biden for high prices, an unprotected southern border and global instability.

Caucus captains are given a list of 25 neighbors and responsible for delivering at least 10 to a caucus. Key between now and the caucuses is “grinding away at recruiting caucus captains and training them,” said Alex Latcham, the campaign's early state director whose background is in Iowa politics.

Other candidates also claim to have the backing of strong organizations.

DeSantis entered the race to the national fanfare of a big-state governor who had won a crushing 2022 reelection victory and is pushing through conservative priorities in a traditional swing state. But he faltered during the summer and fall, with several shake-ups in his campaign and overall strategy.

Still, the main super PAC backing him, Never Back Down, is the largest political operation on the ground in Iowa and claims to have tens of thousands of signed support cards for DeSantis, who has said he plans to win the caucuses.

Haley won a second look from some in Iowa after early fall debate performances. Her candidacy had little apparent support on the ground in Iowa but is now supported by Americans for Prosperity Action, the political arm of the well-heeled conservative Koch Brothers network. AFP Action backed Haley in late November and began knocking on doors for her this month.

In a sign that she's still trying to reintroduce herself to Iowans, Haley began a recent event by retelling her early life’s story to an audience of about 400 in suburban Des Moines near word for word as she did on her first Iowa trip as a candidate 10 months ago.

DeSantis remains the primary focus of the Trump campaign's attacks. Trump, who continually has accused DeSantis of disloyalty for running against him despite the president's 2018 endorsement of him in Florida, has long sought to bury the governor in Iowa. Despite Trump's markedly different to DeSantis' traditional county-by-county effort and fewer overall visits, the president's Iowa push appears to have kept him well ahead.

Sondra Michels said she had long avoided politics before this year. She plans not only to caucus for the first time but to be a caucus leader in her precinct in Walcott, an eastern Iowa town known for being the home of the world’s largest truck stop.

“We’ve got to see him win here and keep going,” said Michels, 49. “He had the prices lower and we were safer.”

News from © The Associated Press, 2023