Standing in front of a jam-packed room at the Iowa headquarters of a super PAC supporting his White House bid, Republican presidential candidate Ron DeSantis stressed "we've done it the right way."

The Florida governor has spent much of his time and resources in Iowa, the state whose caucuses kick off the GOP presidential nominating calendar.

And with his presidential campaign arguably on the line in Monday night's caucuses, DeSantis was urging his supporters to brave the frigid below zero temperatures that are punishing the Hawkeye State to show up and vote.

"It’s going to be cold. It’s not going to be pleasant. But if you’re willing to go out there and you’re willing to fight for me, if you’re willing to bring people to the caucus, if you’re willing to brave the elements and be there for the couple of hours you have to be there, if you’re willing to do that, if you’re willing to fight for me on Monday night, then as president I’ll be fighting for you for the next eight years," DeSantis emphasized.

WHAT THE FINAL POLL BEFORE MONDAY'S IOWA GOP PRESIDENTIAL CAUCUSES SHOWS

DeSantis stands in third place in the latest polls ahead of the Iowa caucuses

Republican presidential candidate Florida Gov. Ron DeSantis, right, takes the microphone after being introduced at an event in West Des Moines, Iowa, Saturday, Jan. 13, 2024. Also on stage with him are Iowa Gov. Kim Reynolds, left, and DeSantis wife, Casey DeSantis. (AP Photo/Pablo Martinez Monsivais) (AP Photo/Pablo Martinez Monsivai)

Supporters who showed up in the blizzard to watch DeSantis on Friday morning in Ankeny said they'd brave the frigid tempertures to caucus on Monday night.

"I will be for sure. And the people that I know will be. A little bit of cold can’t keep you away," Brian Miller said.

An Linda Murphy emphasized "It’s important. We need people in numbers to come out Monday. We’re Iowans. We can handle it."

DeSantis, who was convincingly re-elected to a second term as Florida governor 14 months ago, was once the clear alternative to former President Donald Trump in the Republican White House race. For months, he was solidly in second place behind Trump, who's the far-and-away front-runner in the latest Iowa polls and in national surveys.

However, after a series of campaign setbacks over the summer and autumn, and after getting hammered by negative ads, DeSantis saw his support in the polls erode.

Former South Carolina Gov. Nikki Haley, who served as ambassador to the United Nations in the Trump administration, grabbed momentum during the autumn and has caught up with DeSantis for second place in polls in Iowa and in national surveys. 

HALEY KNOCKS MEDIA EXPECTATIONS BUT LOOKS TO ‘BIG SHOWING’ IN IOWA

Haley also surpassed DeSantis and surged to second place and narrowed the gap with Trump in New Hampshire, the state that holds the first primary and second overall contest in the GOP nominating calendar, eight days after Iowa's caucuses.

Nikki Haley says she spoke with Chris Christie Thursday morning but didn't ask for his endorsement

Former ambassador to the United Nations and former South Carolina Gov. Nikki Haley, a 2024 Republican presidential candidate, stands for photos with supporters and other Iowa voters at a campaign event in Ankeny, Iowa on Jan. 11, 2024. (Fox News - Paul Steinhauser)

Last month, in multiple interviews, even though he was down double digits in the polls to Trump in Iowa, DeSantis predicted victory in the state where he's stopped in all 99 counties.

"We’re going to win Iowa. We’ve got the organization in place," the governor declared in a Fox News Digital interview in Bettendorf, Iowa, a week before Christmas.

While he no longer predicts victory in Iowa, DeSantis has repeatedly said over the past week that he'll "do well" in the caucuses. And the Florida governor is betting that his vaulted ground game in Iowa - which is heavily reliant on the aligned super PAC Never Back Down - will carry him across the finish line.

"We have massive numbers of people. I think we have more commits than anyone's ever had in an Iowa caucus. We have all the counties organized. People that have been involved in this process say it's the best yet," he touted during a Fox News town hall in Des Moines on Tuesday.

BLIZZARD DERAILS IOWA CAMAPIGN EVENTS, WILL BELOW ZERO TEMPS DEPRESS CAUCUS TURNOUT?

Never Back Down highlights that they've knocked on 900,000 doors in Iowa and that they've lined up more than 1,700 precinct captains across the state for the caucuses.

"We have a whole team paid staff, canvassers, volunteers, across the state," Never Back Down's Jess Szymanski told Fox News. "They’ve been here for months…we’ve been building this since July."

But Trump, who narrowly lost the 2016 caucus to Sen. Ted Cruz of Texas, has dramatically stepped up his campaign operation in the state compared to eight years ago.

"We’ve built an operation in over 1,800 caucus locations with straight-up volunteers, neighborhood by neighborhood. They know the area, and they know who’s caucusing in their area, and they’ll be following up with them, making sure they vote," Trump campaign senior adviser Chris LaCivita told Fox News.

TRUMP TAKES NO CHANCES AS THE IOWA CAUCUSES APPROACH

"Our focus and our premium has been on people…and we think it’s going to bear fruit in a big way," he predicted.

Donald Trump in Iowa

Former President Donald Trump speaks at a campaign rally at Terrace View Event Center in Sioux Center, Iowa, Friday, Jan. 5, 2024. (AP Photo/Andrew Harnik) (AP Photo/Andrew Harnik)

Haley is relying on the political wing of the powerful grassroots network from the influential conservative group Americans for Prosperity for much of her ground game efforts in Iowa.

Speaking with supporters on Friday, Haley acknowledged "I know that on January 15th, it is going to be negative 19. I know it's asking a lot of you to go out and caucus, but I also know we have a country to save. And I will be out there in the cold. And I know Iowans take this in a very serious way."

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In a boost of adrenalin for Haley and blow to DeSantis, she edged him 20% to 16% for a distant second place behind Trump in the final Des Moines Register/Mediacom/NBC News poll of likely Republican caucus goers, which was released Saturday night.

The highly anticipated and closely watched survey, conducted by longtime pollster Ann Selzer, has a well-earned tradition of accuracy in past GOP presidential caucuses, and is considered by many as the gold standard in Iowa polling. 

As a blizzard hits Iowa, Ron DeSantis keeps campaigning

Florida Gov. Ron DeSantis, a Republican presidential candidate, takes a selfie with a supporter at a campaign stop in Ankeny, Iowa on Jan. 12, 2024 (Fox News - Paul Steinhauser)

The poll was the second straight to suggest DeSantis had slipped to third place. But DeSantis continues to sound confident, telling Fox News on Friday that his supporters are "motivated, they're passionate, and they're going to show up."

"What about the broader electorate? I just don't know. But I'm confident our people are going to come out strong," he predicted.

And DeSantis seemed to embrace his current standing.

"I kind of like having lower expectations, to be honest with you," he added. "I've been an underdog my whole life and everything I've ever done."

And looking ahead to Monday, he told this reporter "I'd rather be underestimated and let the chips fall where they may."  

Fox News' Clare O'Connor, Deirdre Heavey, and James Levinson contributed to this report

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