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Former U.S. Rep. Mark Sanford has not decided if he will mount a 2020 presidential run against Donald Trump. The president seemed to laugh at the idea on Twitter late Tuesday. File/Staff

Mark Sanford hasn't decided if he's running against Donald Trump in 2020, but already the president is mocking the idea of facing Sanford — or any other Republican challenger.

In a tweet sent late Tuesday, the president referred to the former South Carolina congressman and governor as "Mr. Appalachian Trail" in a dig at Sanford's 2009 extramarital affair with an Argentine journalist when he was governor.

Trump also predicted he would handily win against any challenge from within his own party, including from the two declared GOP challenge candidates, former Massachusetts Gov. Bill Weld and former Illinois congressman Joe Walsh.

"Can you believe it? I’m at 94% approval in the Republican Party, and have Three Stooges running against me," Trump tweeted, referring to his potential opponents. 

Then, Trump pivoted to Sanford.

"One is 'Mr. Appalachian Trail' who was actually in Argentina for bad reasons," Trump wrote.

"Another is a one-time BAD Congressman from Illinois who lost in his second term by a landslide, then failed in radio. The third is a man who couldn’t stand up straight while receiving an award. I should be able to take them!"

After learning about the tweet, Sanford decided to tweet back — something neither Weld nor Walsh did in the immediate aftermath of the president's comments.

"So ready for a President that can move beyond either self praise or put down to one who will focus on the debt & deficit that have gone wild under his time in office. Spending 27% above Obama & deficits even higher. It’s time for a change," Sanford tweeted.

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Trump has famously — and repeatedly — taken aim at Sanford in the past. 

In a late-afternoon tweet on the day of Sanford’s 2018 Republican primary loss, Trump asked state voters to replace Sanford with Katie Arrington, going so far as to say Sanford is "better off in Argentina."

While campaigning for Gov. Henry McMaster in South Carolina, Trump again brought up Sanford's extramarital affair, an incident forever tied to Sanford’s lie that he was "hiking the Appalachian Trail" when he was on a trip to Argentina to see his mistress.

"The Tallahassee Trail – must be a beautiful place. Unfortunately, he didn’t go there," Trump said, mixing up the reference.

Sanford is scheduled to travel to Iowa, the first presidential nominating contest in the country, on Wednesday and Thursday.

Sanford has said he will decide whether to run for president by Labor Day.

Reach Caitlin Byrd at 843-937-5590 and follow her on Twitter @MaryCaitlinByrd.

Political Reporter

Caitlin Byrd is a political reporter at The Post and Courier and author of the Palmetto Politics newsletter. Before moving to Charleston in 2016, her byline appeared in the Asheville Citizen-Times. To date, Byrd has won 17 awards for her work.

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