GEORGETOWN, S.C. — Down along the drowning marshlands and shrinking beaches of this sodden state, the climate candidate is searching.

What he’s looking for is not easy to find: relevance.

With each stop, California billionaire Tom Steyer’s campaign through South Carolina is seeking to separate from a cramped Democratic presidential field — before it’s too late.

He needs a way.

A path.

If it is to begin, it must begin here, Steyer knows. Seldom have a candidate and a locale been more neatly matched. Steyer — the Cassandra of a broiling world. South Carolina — a state balanced perilously at the edge of a rising sea, where people in cities such as Charleston have grown weary of streets turned to streams by mere rainstorms.

“We’re talking about saving the world,” the 62-year-old Steyer says Thursday in an interview with The Washington Post.

But it’s not enough to talk about the peril facing the planet from climate change, he says, reclining in a dowdy, somewhat on-message ethanol flex-fuel Dodge Caravan that he calls the “Glamour Mobile.” (At home in San Francisco, Steyer says he’s been driving a hybrid and composting for years, natch.) The climate message has to hit people in the gut, he reasons, and he finds it “somewhat amusing” that people are content to say we’re facing an “existential crisis.”

“What is that? Like a Camus thing?” he says, referencing the French author Albert Camus. “There’s no blood and guts in the words ‘existential crisis.’ ”

He feels the same way about “pollution.” Not scary enough. He prefers “poison.”

For all the millions Steyer has shoveled into a campaign tailor-made to appeal in places such as South Carolina — one of America’s most vulnerable coastal states — he can feel the head wind. He’s read the press clips. They say he’s an also-ran. A non-factor — especially after disappointing showings in the first three contested states: Iowa, New Hampshire and Nevada.

Don’t believe them, he keeps saying. At a Mexican restaurant called Nacho Hippo in Myrtle Beach, where the crowd has grown so large that people are being turned away at the door, he counsels against listening to media chatterers who claim the only viable options for his party are a democratic socialist (Sen. Bernie Sanders of Vermont) and “the former Republican mayor of New York” (Mike Bloomberg).

In Georgetown, the picturesque small town at the confluence of the Great Pee Dee and Waccamaw rivers, Steyer makes a pitch for help in proving the media wrong. The time is now, he urges. Saturday, when voters head to the polls for the South Carolina primary, is likely to offer the best measure yet of whether he can be a major player as the nomination race moves forward or a forgotten figure.

“I have to show I can do it to change their narrative,” Steyer, who rose to prominence in 2018 with his advertising campaign calling for Trump’s impeachment, tells the audience at Bethel AME Church.

In the audience, the Chirping Birds are nodding with approval. These anti-single-use-plastic crusaders from the nearby beach towns along South Carolina’s Grand Strand like that a reusable water bottle has been set out for Steyer to use during his talk. The well-placed receptacle resonates with them, and he’s speaking their language. But they’re less than enthused that plastic water bottles, arrayed on a table festooned with “Steyered Up” signs, are being offered to attendees.

“I refused,” a founding Chirping Bird Society member, Goffinet McLaren, says.

(Later, Steyer says in an interview, that he “hates” plastic water bottles and has banned them from events his campaign controls and from his business offices. He affects a whiny voice to mimic staffers who complain that they want to drink Perrier from plastic bottles. They’ve adjusted, he says.)

Steyer, an unconventional progressive candidate who made his fortune running a hedge fund and has never held elective office, uses rhetoric that some politicians would try to avoid. For one, he says, he likes “rules.”

“That’s not a bad thing,” he says. “That’s called government.”

In California, where Steyer lives in Sea Cliff, an ultraexclusive San Francisco neighborhood with a horizonless view of the Pacific, they’ve banned single-use plastic grocery bags. He’s certain other places would embrace similar restrictions.

“Actually,” he says, “you don’t even notice.”

Steyer’s wealth has made him a target in the Democratic nomination race, dragging him into a kind of Bermuda Triangle of billionaires, along with Bloomberg and the man he hopes to unseat, President Trump. Steyer, who has pledged to give his fortune to charity during his lifetime, brushes off criticisms from some opponents and from commentators who accuse him and Bloomberg of trying to buy an election with their personal wealth. He doesn’t think voters care.

“Most Americans want to be successful,” Steyer says in an interview.

On the campaign trail, Steyer is careful to differentiate himself from Trump, saying he built a business from scratch, while Trump was the scion of a wealthy real estate empire. In Steyer’s business career, he says, he’s crunched the numbers, doing analyses about how to make money has a calming effect on him.

“It’s very relaxing for me,” he says. “There are right and wrong answers.”

The millions that Steyer has spent, and the professional staff he’s assembled, haven’t stripped the campaign of an occasional seat-of-the-pants feel. At a jazz club fish fry on Thursday, he calls out from a nearby seat while his wife, Kat Taylor, is making impromptu remarks.

“How about a song!” Steyer says.

Within moments, she’s belting out an old Billy Joel tune.

“I have seen that sad surrender in my lover’s eyes/ And I can only stand apart and sympathize/For we are always what our situations hand us/It’s either sadness or euphoria.”

She ends with an ad-lib shout: “Euphoria is where we’re all going!”

Taylor can hit the high notes. Steyer’s voice is more of a perma-rasp, as if he’s battling a slight but persistent cold that arrived and never went away. He tends to wear black jeans low on the hips, a beaded, triangle-patterned belt and his ever-present, signature Scottish plaid tie — practically the only tie he ever wears in public, whether on the debate stage or on the trail.

“I have used it as a napkin,” he quips in an interview. “I don’t think it’s disgusting. Do you?”

His gestures can be slightly stiff, but when he works himself into an impassioned riff he bobs up and down. The fingers on his right hand spread wide, he sometimes punctuates each word with a slight chop.

This.

Is.

What.

We.

Can.

Do.

In a state where it’s almost impossible not to consciously, or subconsciously, adopt some aspect of the local cadence, he isn’t one to roll out colloquialisms. He won’t rely on a “terrific personality” to bend Republicans in Congress to his will. He uses words such as “intentionality.” He embraces his inner nerd.

“I actually like numbers, as crazy as that might sound,” he tells his audience in Georgetown.

In his own way, this would-be president — who can appear stilted and rigid on a television screen — can come off as, well, authentic in person. McLaren, the Chirping Bird, had arrived in Georgetown leaning toward Sanders but left leaning toward Steyer.

“He’s a genuine gentleman,” says McLaren’s husband, Ian, a former sporting goods executive.

Whether gentlemanliness and a love of numbers translates into votes is the question now. Steyer has generally been stalled in polls behind Sanders and former vice president Joe Biden, whose candidacy got a big boost this week when he was endorsed by a South Carolina kingmaker, U.S. Rep. James E. Clyburn.

Biden gets the overwhelming majority of standing ovations at a gathering of African American ministers organized by Al Sharpton’s National Action Network in North Charleston, which draws all the candidates on the South Carolina ballot. But Steyer offers some “aha” moments as he tries to catch up with the poll leaders.

After the event, Chris Berry — a retired telephone company technician — says without prompting that the topic that stood out most for him was Steyer’s avowed support for slavery reparations. Still, Berry says, he’s voting for Biden, who drew his admiration for the quiet empathy he showed while he was vice president during the aftermath of the 2015 Emanuel AME Church massacre in Charleston.

Berry’s friend, Roy Gilliard, a retired fast-food executive, came away impressed by Steyer’s pledge to pump billions into historically black colleges and universities and says he wants to learn more about the bank that Steyer and his wife founded to give loans to businesses owned by African Americans, Latinos and woman who faced discrimination in the banking system.

But it was Steyer’s climate-change message that hit closest to home for Gilliard, who missed out on performing the role of Bono in the play “Fences” because the roads were so flooded in Charleston that the cast and the audience couldn’t make it to a community theater — a common occurrence in the flood-plagued city.

“In Los Angeles, they plan around traffic; in Charleston, we plan around floods,” says the Rev. Nelson B. Rivers of Charity Missionary Baptist, who was one of the hosts of the ministers event where Steyer and his opponents all spoke this week.

Gilliard and Rivers are as urgent as Steyer for a solution. Steyer says he’ll declare a national climate emergency on his first day in office. For now, he can only sound an alarm to urge government action, citing dire predictions, such as a recent J.P. Morgan report that warned of “catastrophic outcomes where human life as we know it is threatened.”

There’s no time to wait, Steyer says: “There’s a clock ticking.”