If it’s South Carolina, it must be crunch time. This is the role we expect of the Palmetto State. This is where front-runners, Mitt “2-and-0” Romney being the 2012 edition, come to seal the deal with Republican voters in Saturday’s primary. And this is where challengers try to hurl themselves in the way.

Former Utah governor Jon Huntsman Jr., in the days before his apparent decision to leave the race, was doing his hurling in the Honeycomb Cafe. To understand why, look at the breakfast plate of Republican voter Alana Knuff, who is eating a hearty order of grits and . . . quiche.

“I wasn’t born and raised here,” Knuff, a Boston native, explained unnecessarily at the event last week in this tidy planned community on Charleston’s outskirts.

Few of the 100 or so voters crowding the restaurant were born here. A man nearby dabbed syrup from a red Ohio State sweater. This is coastal Carolina, where newly minted Southerners, mostly retirees from colder climes, have created some of the state’s most moderate Republican enclaves during a decade of rapid population growth. If South Carolina were to contain any potential Huntsman Country, it would have been somewhere amid the golf courses and marshlands stretching between Myrtle Beach and Hilton Head.

“I’ve got to get my Southern accent going,” said Huntsman, bouncing slightly on his feet as he addressed the diners. Trim, tanned, and wearing a blazer and open-collared red shirt, he looked right at home in these resort environs, like a successful ophthalmologist just in from some morning tennis. “South Carolina is going to play a critical role,” said Huntsman, who barely registered a pulse in state polls.

Already his campaign was down to life-support; he and his wife, Mary Kaye, arrived in a one-car caravan for just the one South Carolina event before winging off to a last-ditch fundraiser in Manhattan (at the house of a woman named Rothschild, who almost certainly doesn’t take grits with her quiche).

The South Carolina endgame is going to be a rush job this year. The ever-tightening primary schedule has provided only 11 days after New Hampshire for the non-Romneys to sniff out voters not already on the Romney Ride-Along: mainly evangelicals, military voters, frustrated tea party activists, independents.

Texas Gov. Rick Perry is stalking the country-cookin’ places around the mid-state Piedmont. After finishing last among major candidates in Iowa and finding fewer than 2,000 votes in New Hampshire, he’s looking for love along the steam tables of South Carolina: Duke’s Barbecue, Lizard’s Thicket, Doc’s, the Squat & Gobble.

“I was sharing with some folks out on the porch before I came in that Leesville is not that different from where I grew up,” Perry said to a crowd at Shealy’s Bar-be-cue in this tiny town west of the state capital. He talked happily about the washtub where he took baths on his boyhood home’s porch. He highlighted his Air Force service. He called Romney a “vulture capitalist,” a label designed to resonate in a manufacturing state with an unemployment rate of almost 10 percent. Perry wants more oil and gas pulled from federal lands, but he also hails “solar, wind and nuclear,” which, in the way of Texas governors, he pronounces “nuke-u-lar.”

Perry clearly feels that he is among friends, comfortably quoting scripture under a watercolor of a bird dog with a limp dove in its mouth. The two accordion walls of the spillover dining room were pushed open to accommodate a crowd of about a 150 who responded warmly.

A day later, Newt Gingrich is in a packed glass-walled room at the Beacon, a sprawling drive-in in Spartanburg. A lighthouse looms over a parking lot thick with the smell of onion rings. Gingrich and his wife, Calista, are bathed in camera light, as is a placard next to them promoting the weekly “men-a-plenty Bible study.”

The former House speaker didn’t mention Romney by name, even as he and his supporters were filling the airwaves with attacks on the front-runner as an insincere conservative and rapacious capitalist. Instead, he contrasted himself to President Obama, which he summarized as “the difference between the Declaration of Independence and the radical writings of Saul Alinsky that he admires.”

Gingrich had time for only two questions, one of which came from Zach Maher, 13, who said he had worked on it for two days: “Why do liberals want to take God out of our society . . . which was built on Christianity?”

Gingrich answered at length about “anti-religious judges” before crafting a short history of Pope John Paul II’s role in bringing down the Soviet Union. “Literally as the Polish people began to remember their Christianity, they began to melt their communist bonds.”

Down in Beaufort, not far from the Marine Corps’ Parris Island boot camp, there was also an end-time feel to Rick Santorum’s remarks behind the Beaufort Yacht Club. Speaking in cheerful tones beneath a live moss-draped oak, the sweater-vested Santorum lamented federal intrusions in the economy, health care and even light bulbs.

Do you want the federal government “to tell you what kind of toilet to flush?” asked the former senator from Pennsylvania. “Is this what the folks over on Parris Island want to fight for? Hell, no.”

But Santorum was out-despaired by a questioner.

“This is more treacherous than the debate in this city before the Civil War began,” said a man, referring to the 1861 unpleasantness 100 miles away at Fort Sumter.

“Thankfully, I’m not as pessimistic as you are,” replied Santor­um, who has emerged as a favorite among evangelical leaders.

Romney, meanwhile, is not doing so many barbecue stops or yacht club appearances. To the front-runner goes the boisterous pageantry of the big venue. About 500 people filled a 5,000-square-foot wedding hall in downtown Columbia last week, waiting to meet the Mitt.

There were a lot of men wearing blue blazers over open collars and khakis and women donning stylish square eyeglasses. It was a crowd that looked incomplete standing around and chatting without tumblers filled with ice cubes clinking in their hands. One man, taking pictures with his iPhone, wore a bird-hunting vest.

Romney — black blazer, open collar — let South Carolina Gov. Nikki Haley do the railing against “Republicans talking like Democrats against the free market.” Romney, who is leading in the polls, kept his rhetoric trained on Obama, except when he began reciting the lyrics to “America the Beautiful” — the obscure ones.

“I love the verse that goes ‘O beautiful for heroes proved,’ ” the former Massachusetts governor said, not singing. “ ‘In liberating strife, Who more than self their country loved, And mercy more than life.’ Do we have any veterans in the room?”

He wrapped up, to huge applause, with a “Thanks, you guys!” Without stepping down from the stage, but shucking the jacket, he spent more than half an hour shaking hands and passing babies back and forth, and also a couple of heavier toddlers.

“I’m crazy about him,” said Blanche Gibbes, a stately 91-year-old Columbia matron in a gray sweater and matching hair. She stood for more than an hour to see Romney, although she said that any Republican will get her vote in November. “We’ve got to get this country back in order. This depression feels so much different than the last one.”

That would be the Great Depression. She was a teenager for that one.

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