Nancy Mace predicts ‘double digit’ victory over Trump-backed GOP primary challenger Katie Arrington in SC

SUMMERVILLE, S.C. - Republican Rep. Nancy Mace of South Carolina says she’s confident she won’t become the first incumbent knocked out by a primary challenger supported by former President Donald Trump.

"We're gonna win by double digits," Mace predicted in an interview with Fox News "That's what everything's looking like."

Mace, the freshman representative in South Carolina’s 1st Congressional District – a key swing seat – is facing a primary challenge from Katie Arrington,  a former state lawmaker backed by Trump, who nearly 17 months removed from the White House remains the most popular and influential politician in the GOP.

"I'm feeling cautiously optimistic. Of course, the only poll that matters is the one on election day," Mace cautioned in an interview on Sunday at a campaign event with former ambassador and former South Carolina Gov. Nikki Haley. 

But she then touted that "we have overwhelming support…we are we're cresting at the end here."

Mace was one of the earliest supporters of Trump’s 2016 presidential campaign. And she was not one of the ten House Republicans to vote to impeach the then-president nearly a year and a half ago for fueling the deadly Jan. 6, 2021 storming of the U.S. Capitol by right wing extremists and other Trump supporters who aimed to disrupt congressional certification of now-President Biden’s 2020 election victory. But Mace did publicly say that Trump’s rhetoric leading up to the storming of the Capitol "put all of our lives at risk."

TRUMP TARGETING OF NANCY MACE FUELS SOUTH CAROLINA REPRESENTATIVE'S FUNDRAISING

And last October, Mace was the lone South Carolina Republican to join congressional Democrats in voting to hold former Trump White House senior aide Steve Bannon in contempt of Congress for defying a subpoena issued by the House select committee investigating the riot at the Capitol. 

Trump endorsed Arrington as she launched a primary challenge in February, and he praised Arrington and pilloried Mace at a rally in South Carolina in March. An Arrington TV ad uses a clip of Trump from the rally charging that Mace "is a terrible person" and "has no idea what she’s doing." And last Tuesday he took aim at Mace once again in a tele-rally for Arrington.

Arrington told Fox News that Trump’s "the heart of the Republican Party right now. He represents hope that there's going to be a better tomorrow…we in this district want someone who's going to represent the three core values. We believe in faith, family, and freedom."

"And that's why Donald Trump endorsed me, and that's why this district on June 14 will endorse me in the ballot box," she predicted.

CLICK HERE TO WATCH KATIE ARRINGTON INTERVIEW WITH FOX DIGITAL

Arrington was interviewed as she and a couple dozen volunteers huddled in her Summerville, South Carolina home called voters to seek support in the final hours of the primary campaign.

The First Congressional District, which includes much of coastal South Carolina including the fast-growing suburbs surrounding the city of Charleston, was represented for much of the last decade by former Republican Gov. Mark Sanford, who was a vocal Trump critic.

Arrington, with Trump's support, challenged and defeated Sanford in the 2018 GOP primary. But she lost the general election by a razor-thin margin to Democrat Joe Cunningham, during a very rough election cycle for the GOP. Two years later, in 2020, Mace narrowly edged Cunningham as the GOP flipped the seat back from blue to red.

"My opponent is the one that lost his seat to a Democrat for the first time and in 40 years in 2018," Mace told Fox News.

WATCH: NANCY MACE SPEAKS WITH FOX DIGITAL

And speaking to supporters at Halls Chophouse in Summerville, she spotlighted that "getting the majority back in this country runs through swing districts - swing districts like the First Congressional District. If we're gonna have a Republican majority in November to reverse what Joe Biden has done to our country in a year and a half, we have to win this district."

"And that means we have to nominate someone who knows how to win and I am the only woman in this race on this ballot, who knows how to win the First Congressional District," the incumbent highlighted as she took a jab at Arrington.

Standing next to Mace and introducing her was Haley, who won election and reelection as South Carolina governor before serving as ambassador to the United Nations during the Trump administration. But Haley and Trump are on opposite sides in this high-profile GOP showdown. 

"Nancy Mace is tough as nails. She is running circles around [House Speaker] Nancy Pelosi," Haley told the crowd. "She is not a pushover."

And Haley highlighted that "you may not agree with 100% of everything she does, but she's fighting for you every day and every time whether it's the establishment Republicans, whether it's the resistance Republicans, anybody that thinks that you put Nancy in a box, they're wrong. Because at the end of the day, the only box she cares about the First Congressional District, and she's never forgotten who she works for."

While she’s taken incoming verbal attacks from the former president for months, Mace doesn’t return fire.

Mace, in a video she recorded in February in front of Trump Tower in New York City and posted to social media, highlighted her support for the former president. And in an interview with Fox Digital in April, the most critical thing the representative said about Trump was that "I think he’s gotten bad advice and that’s problematic."

On Sunday, Mace highlighted "I'm the only candidate in this race that supports America First policies. We have a lot that we can agree on as Americans, as conservatives, as Republicans, no matter what brand of Republican you are in our country. I put our country first."

CLICK HERE FOR THE LATEST 2022 PRIMARY RESULTS FROM FOX NEWS

Mace and a couple of outside groups supporter her have outspent Arrington to run campaign commercials in the closing weeks leading up to the primary, and Mace’s ads take aim at Arrington over national security and taxes.

And Mace touted her conservative credentials while attacking Arrington’s, arguing that "I have a great record as a conservative I have almost a perfect conservative report card with every conservative group. It was my opponent that scored a 30 when she was a state lawmaker, and last I checked that was a failing grade.

Arrington countered, charging that Mace is "not a conservative. That's why I am running. She turned her back on us in the district. She turned her back on Donald J. Trump. And that's why I'm running in this district for a true conservative - somebody who's going to stand for the values that we hard hardworking Americans, the forgotten folk, care about."

The most recently public opinion survey in the race indicated Mace up by single digits, but internal polling by the Mace campaign suggests she’s leading by double digits and above the 50% needed to avoid a runoff election later in June.

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Asked how she can close the gap, Arrington pointed to a group of volunteers right behind her, phone banking to make sure supporters get to the polls. 

"These guys, grassroots," Arrington said. "Inside the house right now I have about 30 volunteers. This crowd has been out here. This campaign is about the people. We the people. It's totally a grassroots campaign. I mean, I have people in there dialing right now. I've been dialing most of the day. We've been out, door knocking."