Ask Mark Sanford if any Republican can knock off President Trump in the Republican primaries and he’ll give you an honest answer.

“I always like to be real, and I don’t think anybody’s going to beat Donald Trump. That’s my personal opinion,” the former South Carolina governor and congressman said in an interview Monday with Fox News.

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But Sanford, who last week announced he was taking 30 days to decide whether to launch a primary challenge against the president, said that if he runs, it’s not about ousting the president. At least not completely.

“I think it’s about trying to force a larger national debate and a debate within Republican circles,” he said.

That debate, for Sanford, centers on the national debt, which now stands at over $22 trillion.

Sanford warned that we’re “walking our way towards the most predictable financial crisis in history of our country if we don’t do something about the government spending issue. It is profound.”

And the longtime deficit hawk predicted that “we’re setting ourselves up for a real fall that will hurt our retirement accounts, our savings accounts, our jobs and our way of life.”

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Sanford’s mission, if he launches a primary bid, is to take the GOP back to fiscal issues, targeting the national debt and spiraling government spending.

“The idea of financial sanity, the idea of financial prudence, was a linchpin to the conservative movement and by extension the Republican Party, “ he said. “That has been lost of late.”

And he noted “I was just dumbstruck to hear Rush Limbaugh’s comments over the weekend that deficits don’t matter. It is something that we have to get back to.”

Asked what his deciding factors will be in launching a primary challenge, Sanford listed viability.

“The energy, resources, and the people who come my direction versus not, will tell me a lot as to how viable such a run will be. And by viable, I don’t mean necessarily beating the president, but I mean viable in terms of getting a voice and message out there that I think needs to be heard,” he said.

And he argued that “we need to have a conversation as Republicans about what we’re about.”

In a party dominated by Trump, such ideas aren’t welcome words, especially in his home state.

After Sanford announced he was mulling a primary challenge, South Carolina GOP Chairman Drew McKissick responded “the last time Mark Sanford had an idea this dumb, it killed his Governorship….This makes about as much sense as that trip up the Appalachian Trail.”

The ‘Appalachian Trail’ is a reference to Sanford’s original excuse of where he was during a week-long disappearance in June 2009. It was later revealed that Sanford was out of the country, having an affair with an Argentinian woman. The episode ended his marriage and derailed the political career of the popular two-term governor who was considered an early leading contender for the 2012 GOP presidential nomination.

But politics is full of second chances and the former governor won back his old congressional seat in a 2013 special election. He won re-election in 2014 and 2016. But Sanford, a vocal Trump critic, was targeted by the president in his 2018 re-election and lost a primary challenge to a pro-Trump candidate.

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Asked if his possible primary challenge against the president is revenge for his 2018 loss, Sanford quickly answered: “Absolutely not.”

Sanford noted that he was concerned with the “send her back” chants at a Trump rally in North Carolina last week that were directed at Democratic Rep. Ilhan Omar of Minnesota, whom the president days earlier on Twitter had urged to go back to her native country, fix things and return to "show us how it's done." Democrats and even some Republicans have called the tweets racist.

After condemning the chants in the wake of the ensuing criticism, Trump later called the crowd “patriotic” and resumed his attacks on Omar and three other liberal freshman congresswomen known as ‘the squad.’

Sanford said the chant is “a long way from what we all learn about when we go to church Sunday, which is ‘we’re to love God with all our heart, soul and mind, we’re to love our neighbors as ourselves.’”

“It’s at odds with what the good book says on that front,” he added.

Sanford said it’s likely he’ll visit Iowa and New Hampshire – the states that kick off the presidential primary and caucus calendar – during his 30-day listening tour. And he noted that he’s been in contact with conservative Bill Kristol, a leader of the ‘Never Trump’ movement.

If he runs, Sanford would join former Massachusetts Gov. Bill Weld in primary-challenging the president.

Sanford praised Weld, saying “I admire his courage. I admire that he was willing to step out on the ice first while nobody else was even thinking about it.”

Weld, campaigning in New Hampshire on Monday, told Fox News that Sanford “could be a real factor in the southern states, either in the primary or running as a favorite son in the general election. I think he could certainly deny Mr. Trump enough votes in those states so that Mr. Trump will have a hard time winning those states.”

He welcomed a possible Sanford campaign, emphasizing that “the more people who come in, it makes it seem more like a real primary, harder for the president to duck debates.”