Today’s Congress deserves its reputation for uniformity in the ranks. Gender and ethnicity aside, the place is overrun with members priding themselves on their message discipline, policymaking tunnel vision and personal lives scrubbed and shielded from public view. And for the Republicans, of course, unflinching loyalty to President Donald Trump is now the core of the homogenized brand.

So is Hill survival even possible anymore for a member capable of thoughtful departures from his partisan talking points, open to ideological subtlety, with a home life that’s been a national melodrama — and who on top of all that has called out the president on more than one occasion?

Mark Sanford was hoping that, once again, he would be the exception that proves the seeming rules of modern American politics.

Five years ago, he came back to Capitol Hill in an election belying conventional wisdom that cultural conservatives won’t forgive a politician who seeks to return from exile after personal scandal.

But now he’s out. He spent heavily but lost narrowly Tuesday in the Republican primary in South Carolina’s coastal low country, ousted from Congress by a state legislator who focused almost entirely on the incumbent’s Trumpian transgressions.

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So Sanford’s message was altogether different from what he’d hoped: There’s even less political oxygen than it may have seemed for a candid iconoclast hoping to survive in a Republican cloakroom dominated by those comfortable with forgetting long-held conservative beliefs while burnishing their presidential fealty to a high gloss.

“We are the party of Donald J. Trump,” state Rep. Katie Arrington declared at the start of her victory speech. She took slightly more than half the vote and had a winning margin of about 2,600 ballots, narrowly avoiding a runoff with Sanford. Given the district’s solid Republican core, she becomes the prohibitive favorite in the fall.

Being seen as failing the 100 percent loyalty test has already caused a handful of GOP congressional incumbents to stumble badly.

In the House, backbench conservative Robert Pittenger lost his seat in a North Carolina primary last month, his opponent creating a wedge issue out of the congressman’s single “yes” vote on a spending bill that Trump decided afterward he did not much like. And Alabama’s Martha Roby has been forced into a runoff next month, because plenty of her constituents remain furious that two years ago she withdrew her support for Trump after he boasted of assaulting women.

In the Senate, of course, both Jeff Flake of Arizona and Bob Corker of Tennessee decided to retire when their sometimes tart criticisms of Trump threatened to propel them into vituperative, expensive and not necessarily successful primary contests.

Hard decisions

In the closing days of Sanford’s campaign, he sought to emphasize the times he had stayed close to Trump — asserting it was 89 percent of the time. In fact, on the relatively few votes where the president’s position has been clearly understood in advance, just 51 of them between Inauguration Day and Tuesday’s primary, Sanford voted the opposite of what Trump wanted on 15 of them, the fourth highest opposition rate among GOP members seeking re-election.

Beyond his voting record, Sanford has agitated conservatives by questioning the worth of Trump’s border wall, supporting a generous approach to immigrant “Dreamers,” arching his eyebrow at Trump’s protectionist trade moves, encouraging the president to release his tax returns, questioning the depth of Trump’s constitutional understanding, lamenting his complimentary statements about Russia’s Vladimir Putin and describing Trump’s rhetoric as “partially to blame for demons that have been unleashed” in the polarized national discourse.

“It may have cost me an election in this case, but I stand by every one of those decisions to disagree with the president,” Sanford told supporters as the returns came in.

Trump endorsed Arrington on Twitter less than three hours before the polls closed, mockingly reviving the most embarrassing period in Sanford’s life: His disappearance in 2009 from the governor’s office, which he’d then held for six years, to rendezvous with a woman not his wife in Buenos Aires while telling the world he was simply hiking the Appalachian Trail.

“Mark Sanford has been very unhelpful to me in my campaign to MAGA. He is MIA and nothing but trouble. He is better off in Argentina,” the president tweeted, while Arrington “is tough on crime and will continue our fight to lower taxes.”

Sanford, who turned 58 last month, is hardly the only South Carolina politician whose life has become more complicated after crossing the president. Sen. Lindsey Graham spent much of 2016 thinking up clever ways to talk trash about candidate Trump but has now engineered a viable working relationship. As governor, Nikki Haley derided Trump’s efforts to whip up nationalist passions, but now she’s his envoy to the United Nations. Departing Rep. Trey Gowdy has recently chided the president for fomenting conspiracy theories.

Leaning to the right

But like many lawmakers who have opposed Trump on policy matters, it’s generally (but not always) been because Sanford has positioned himself to the president’s right.

A member of the Freedom Caucus, he last year pushed a more limited-government replacement for the 2010 health care law than the administration wanted. On budget-busting grounds, he’s also opposed funding legislation that Trump got behind on matters ranging from opioid addiction treatment to military weapons systems. When he was governor, he famously (if unsuccessfully) went to court in an effort to turn back $700 million in federal economic stimulus spending earmarked for South Carolina.

His small-government fiscal conservatism, though, is partly offset by his support for environmental regulation. Sanford was among just a handful of Republicans who opposed getting rid of Obama administration rules to limit air pollution from oil and gas drilling and water pollution from open pit coal mining.

Unlike so many lawmakers, he’s unafraid when approached by a reporter in a hallway to ponder the actual question asked — not just reflexively spout the talking points of the day. He’s also not afraid to mix it up in the town hall meetings, often packed with activists from the other side, that so many of his colleagues have started spurning as never before.

“It’s part and parcel of the theater that is the political process,” he said in an interview last year. “We better watch out as representatives when we just do the echo chamber routine and we will only go before groups that we think are safe for us.”

A survivor

Sanford had also been a remarkable political survivor. Having arrived in Congress with no prior electoral experience when he was just 34, he is now among just nine Republicans (out of 73) first elected 24 years ago in the “Contract With America” who remain in office. (His defeat and a pair of retirements will shrink that roster next year.)

Sanford learned frugality early on; legend has it that his father, a cardiologist first at Johns Hopkins in Baltimore and then in Florida, had his family sleep in the same room to conserve energy and save on the heating bill.

Sanford was a real estate banker in New York and a real estate developer in Charleston before launching his first political campaign, winning an open and reliably Republican seat. (His standing as a neophyte was such that he found himself at freshman orientation wondering how he ended up on the Joint Economic Committee, a second-tier oversight panel he readily conceded he knew nothing about, admitting he also did not know he was expected to lobby for committee assignments.)

Honoring a campaign promise to stay in the House no more than three terms, and after being in the vanguard of members who lived in their offices as a signal of outsider frugality, Sanford headed back home and two years later ousted the incumbent Democratic governor, Jim Hodges.

By his second term, there was talk of a presidential candidacy, as his promotion of spending cuts and tax cuts got him labeled the best governor in America by the libertarian Cato Institute. But that all came to a sudden halt in June 2009, when he professed to have found his “soul mate” and it was revealed the search for love had involved the use of taxpayer dollars for travel to Argentina. He was censured by the state legislature and divorced from his wife, Jenny.

He served out his term and went back into business, but in 2013 was quick to enter the race for his old House seat, opened when Tim Scott moved to the Senate. Despite allegations he’d trespassed at his ex-wife’s home, which prompted the House GOP campaign organization to pull its financial support, Sanford prevailed by 9 points over Elizabeth Colbert Busch, a university official and sister of satirist Stephen Colbert.

Sanford said he and María Belén Chapur were engaged when he came back to Congress, but they announced their breakup the next year.

Two years ago he easily defeated Democrat Dimitri Cherny, who campaigned with a Sen. Bernie Sanders tattoo on his left arm — but who ran this week as the third candidate in the GOP primary, garnering 4 percent of the vote.

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