Former congressman Mark Sanford (R-S.C.) said he's pondering a 2020 primary challenge to President Trump. (Bruce Smith/AP)

Mark Sanford’s promising political career has been declared dead — twice. Now, the Republican former governor and congressman from South Carolina says he is considering a presidential bid that would pit him against his party’s leader.

That would put him on a collision course with someone whose political trajectory has had some odd parallels with his own over the past decade, some of which could make an already difficult trajectory for Sanford to knock President Trump off even harder.

Late in the past decade, Sanford was a popular governor who was seen as a promising Republican contender for higher office when he was brought low by revelations of an extramarital affair.

After news of the affair broke, former Fix reporter Chris Cillizza wrote in 2009: “Sanford’s public announcement punctuates a strange and winding series of events that caused confusion within the state government and considerable chagrin among the Republican Party, which saw its second potential 2012 candidate in as many weeks brought low by infidelity.”

At that time, Trump was in the first years of his third marriage and was elevating his political profile through media appearances promoting the birtherism conspiracy about candidate and then President Barack Obama.

Sanford, a conservative Christian who was known to have had presidential ambitious, had a national profile that was rising when, in 2009, the then-governor disappeared for nearly a week. His staff originally said he was hiking the Appalachian Trail, but Sanford eventually held a news conference in which he tearfully revealed he was in Argentina visiting Maria Belen Chapur, a former television correspondent with whom he was having an extramarital affair.

The controversy led the South Carolina General Assembly to censure Sanford, and he resigned as chairman of the Republican Governors Association. He was able to complete his second gubernatorial term, though the cloud remained and his marriage ended in divorce. He managed a notable comeback in 2013, winning a congressional seat he had previously held when its occupant, former congressman Tim Scott (R.-S.C.), was appointed to the U.S. Senate.

Sanford backed Trump in the 2016 election, not without some reservations, but quickly emerged as one of the president’s most vocal critics on the right — something Trump did not respond to very well. According to FiveThirtyEight, Sanford was among the five GOP lawmakers who voted against Trump the most. The president, who is famously averse to slights, endorsed Sanford’s opponent in the primary heading into the 2018 election. Sanford lost to another Republican (who went on to lose the seat to a Democrat in the general election).

All the while, Trump was on his path to the White House and to taking over, and then tightening, his grip on the Republican Party.

Trump, a former playboy known for his celebrity lifestyle, ended up winning the support of white evangelicals in 2016 after a presidential race that allegedly included the use of campaign funds to settle affairs — including one with an adult-film actress just a month after Trump’s third wife had given birth. The president denies the affairs and maintains the support of his base and party leaders.

Much of the criticism aimed at Trump — including from the right — is focused on the president’s character and behavior. That is a problem for Sanford, cutting off one avenue where he could have peeled off support. He will probably have to take a different approach, given his own checkered past.

Sanford said his candidacy would challenge Trump’s handling of the economy, something the president is so proud of that he’s basing much of his reelection campaign on it. But the former lawmaker said Americans have much to be concerned about regarding how little attention is being paid to the federal debt and deficit.

“The place where there is no discussion is the way in which interest is the largest growing expense in the federal government,” he told CNN Tuesday.

While the former lawmaker’s points about the economy and the debt might be valid to some, the Republican Party under Trump is quite different from the days of the GOP when Sanford lived in the governor’s mansion. Losing his 2018 reelection probably taught Sanford that most Republicans back Trump and vote for lawmakers who support the president. There is not much reason to believe 2020 would be any different.