Republican presidential candidates trudged through blistering subzero temperatures in Iowa on Sunday to deliver closing arguments ahead of Monday’s long-awaited caucuses — the first nominating contest in an election year shaping up as a test of starkly competing political visions and American democracy.

Donald Trump, the clear Republican polling leader, offered a grievance-laden and defiant closing pitch in suburban Des Moines in which he lashed out at his main rivals as disloyal, derided the state’s Republican governor and made slashing attacks on his critics. Speaking at one of his few in-person events in the final stretch, he warned his supporters against complacency on what is forecast to be a bitterly cold caucus night.

Nikki Haley, looking to secure a surprise second-place finish that would cement her spot as the clear Trump alternative, hit the trail in the backroom of a barbecue joint in the college town of Ames as she tried to make the case that she has the best chance to win a general election. The former U.N. ambassador made only a brief reference to Trump, reprising her assertion that “chaos follows him,” as she made a more traditional conservative pitch for muscular foreign policy and fiscal restraint.

And Florida Gov. Ron DeSantis (R), fighting for his political survival, argued that he would bring the same political and policy results he produced in Florida to the nation, and he suggested he was the only one in the race fighting for conservative voters’ issues.

The competing appearances across a frigid landscape heralded the end of months of campaigning in a Republican race that has been remarkably static, with Trump at the top and little indication that he is in any serious jeopardy of being dislodged. Monday night’s caucuses, which polls show Trump is poised to win handily, will offer the first electoral test of Trump’s appeal to his party.

“It’s like there’s two things going on: There’s Donald Trump. He’s a former president running for the nomination again. He’s been in control the whole time,” Iowa GOP strategist Craig Robinson said. “And there’s been this secondary contest of who can be the alternative to Trump. And that’s what Iowa is going to figure out.”

The caucuses also represent the unofficial start of an arduous election year that could feature a contentious matchup between a former president under four criminal indictments who has campaigned on themes some regard as more extreme than his first term’s, and a current president dogged by low approval ratings.

For months, the race in Iowa has remained relatively stagnant at the top, with Trump leading in the polls by double digits, including in the final Des Moines Register/NBC News/Mediacom poll. But the survey found Haley surpassing DeSantis for the first time.

Yet it also had some warning signs for Haley, finding that a 61 percent majority of her supporters are “mildly enthusiastic” or “not that enthusiastic” about turning out. Pollster J. Ann Selzer told the Des Moines Register that the data suggests “she looks stronger in the poll than she could on caucus night.”

Trump’s campaign is hoping for a knockout blow in Iowa that will set a formidable tone heading into New Hampshire’s primary eight days later. Sunday’s event in Indianola marked his first in-person campaign event in the state since last weekend — a contrast with Haley and DeSantis, who have held a number of events throughout the week. Trump was originally set to hold back-to-back events on Saturday but canceled, citing Iowa’s weather. He opted for a tele-rally with Attorney General Brenna Bird (R) instead.

As Iowans weigh whether to brave subzero temperatures and dangerous conditions Monday to go out and caucus, Trump, wearing a white hat with “Trump Caucus Captain” in gold font, joked at his rally on Sunday that death was worth the risk because his voters would be caucusing to save their country. And he warned Iowans to act as if he were behind in the polls.

The National Weather Service issued a wind chill warning Sunday from Des Moines forecasting that “life-threatening wind chills” will continue into Tuesday as the Arctic cold air has settled in the area with temperatures “well below zero.”

“This extreme Arctic air combined with breezy winds at times will continue to create dangerous conditions into Tuesday, with wind chill values as low as 45 below zero possible at times,” the warning said.

Voters must arrive at their precincts at 7 p.m. Central time on Monday to hear speeches from the candidates’ representatives before filling out ballots. The detailed forecast from the Weather Service for Monday night in the Des Moines area predicted a low around minus-11, with wind chill values in that area as low as minus-30. Wind gusts, the forecast said, would be as high as 22 mph.

Trump told his supporters in Indianola on Sunday that they would be safe because they would mostly be indoors during the caucus event — not focusing on the potential dangers that they could face on the roads and even walking outside as they try to get to their caucus sites.

He told attendees that “if you vote and then pass away, it’s worth it,” prompting laughter. “You’ll be safe and all. You’re going to be safe. … You’re going to be all indoors, but you’ve got to get up; you’ve got to vote. Because it has nothing to do with anything but taking our nation back, and that’s the biggest thing there is.”

The campaign is counting on voters such as Syndi Powell, a 20-year-old Simpson College student who wore three pairs of socks and two pairs of leggings under her sweatpants to wait two hours in the subzero temperatures to get into Trump’s speech in Indianola. About 600 people were packing into an auditorium hours ahead of Trump’s remarks.

Trump made loyalty a key theme of the speech, suggesting that DeSantis, Haley and Iowa Gov. Kim Reynolds (a DeSantis backer) were disloyal to him. In recent weeks, Trump has sharpened his attacks on Haley, who served in his administration.

“I’m working for you, and she’s working for a lot of other people. People that don’t necessarily love our country so much,” Trump said. He went on to vaguely foreshadow criticisms of Haley that many operatives expect to escalate further as the race moves to New Hampshire. “You’re going to find out a lot about her in the next short period of time,” he said.

During his speech, which was briefly interrupted by climate protesters, Trump hit on similar themes to his previous rallies, including the border, inflation and his false claim that the 2020 election was “rigged.” He described D.C. as a “rat-infested, graffiti-infested s—hole.” Trump took credit for Iowa’s first-in-the-nation status and claimed that “nobody took better care of the farmers than Trump.” And he sought to portray himself as an outsider, despite having been president for four years.

He also leaned into a frequent theme of victimhood, reiterating his allegations of a weaponized judicial system as he faces 91 criminal charges and four indictments. (Special counsel Jack Smith and Attorney General Merrick Garland have said Smith’s prosecutions were made independently of the White House, in accordance with Justice Department rules on special counsels.)

At the event Sunday, North Dakota Gov. Doug Burgum (R) endorsed Trump, becoming the first former candidate in the 2024 GOP field to do so. Trump also received an endorsement from Sen. Marco Rubio (R-Fla.).

Haley has experienced some momentum going into Monday. She centered her pitch on the notion that she has a better chance of beating Biden in November.

“Republicans have lost the last seven out of eight popular votes for president. That’s nothing to be proud of. We should want to win the majority of Americans. But the only way we’re going to win the majority of Americans is if we have a new generational leader. That leaves the negativity and the baggage behind and focuses on the solutions of the future. You don’t fix Democratic chaos with Republican chaos,” she said.

Haley’s allies are hoping that a strong finish in Iowa will help catapult the former U.N. ambassador into New Hampshire, where she has support from Gov. Chris Sununu (R) and polls show a closer race with Trump.

In Ames, Sen. Joni Ernst (R-Iowa) introduced Haley. Ernst has not endorsed in the 2024 race. Still, she lavished praise on the former South Carolina governor, calling her “a leader” because “she is inspiring so many people across the state of Iowa.” Ernst was set to appear later Sunday with DeSantis.

In Ames, Haley joked about her previous trips, when Iowans had laughed at her after she’d remarked that it was cold.

“You would laugh at me,” Haley said. “Now I get it. I get why you were laughing at me, because this is truly cold. But we’re gonna keep on going anywhere and everywhere. We’re gonna go all the way until the last hour.”

Paige Hays, 23, a caucus-goer who lives in Ames, said she liked Haley’s message. “After [Trump] didn’t win the election … it was just like she said: chaos. We should not have people storming the Capitol,” Hays said.

DeSantis, who has struggled in recent months even as he has invested heavily in Iowa, made his closing argument in Cedar Rapids on Sunday in part by emphasizing how he has pushed his conservative agenda in his home state and won a landslide reelection win.

“Just like we did in Florida, we’ll win up and down the ballot,” he said. He echoed some of the same positions as other candidates: a hard-line stance on border security, and criticism of China. “When the chips are down, you can depend on me,” he said.

But much of DeSantis’s speech focused on Trump. He told Iowans that Trump was running on promises he made last election that he hadn’t kept, such as finishing the border wall.

“When I tell you I’m going to do something, you take it to the bank,” he said.

“Donald Trump is pursuing his issues, and those are the issues that motivate him. Haley’s just running on her donors’ issues,” DeSantis said. “I’m running on your issues.”

He pointed out how Trump had attacked Reynolds in an Indianola speech that ended shortly before his began. “Don’t be like Donald Trump and attack a good governor just for doing a good job,” DeSantis said.

A day ahead of the Iowa caucuses, DeSantis appeared on five Sunday morning TV shows, continuing his breakneck pace of interviews and events in the final stretch. Once hostile to the mainstream media, the governor shifted course and embraced a “DeSantis everywhere” media strategy midway through his campaign, blitzing TV, radio and podcasts across the political spectrum.

DeSantis and his advisers have even lashed out at Fox News and other conservative media in recent days, accusing them of carrying water for Trump. Over the weekend, a slew of out-of-state DeSantis allies were in Iowa, many of them helping knock on doors. Among them: Florida Lt. Gov. Jeanette Nuñez (R), Florida Health Care Administration Secretary Jason Weida and DeSantis’s mother.

Asked on the trail Sunday about the potential for an embarrassing finish — with Haley now leading DeSantis in some polls — DeSantis dodged.

“If ifs and buts were candy and nuts, every day would be Christmas,” he said.

Kornfield and Wells reported from Iowa. Scott Clement in Washington and Hannah Knowles and Isaac Arnsdorf in Iowa contributed to this report.