There's a cool rain falling on the South Carolina State House, but it's nothing compared to the storm inside. The date is April 2, 44 days since President Obama signed his stimulus package into law and 24 hours, or so everyone believes, before the nation's governors can no longer claim their full share of the funds—something the Palmetto State has yet to do. Frustrated legislators mill and murmur in the lobby, awaiting the bell that will call them to their chambers for yet another round of anguished debate. Protesters, mostly teachers, wave handmade signs outside the entrance. On the lower level, a receptionist lifts her endlessly ringing phone from its receiver and repeats a single phrase—"The governor's office, hold please"—again and again (and again). Meanwhile, the man himself, Gov. Mark Sanford, sits behind a closed door 30 feet away, pausing in the midst of the crisis to "visit," as he puts it, with a reporter from a national newsmagazine. And he is starting to cry.

Sanford isn't exactly known for his softer side. When Obama unveiled his $787 billion stimulus plan, a flock of ambitious Republican governors promised to fend off large portions of the Washington windfall. But as political pressures mounted, only Sanford stuck to his guns. For the past month, he has boldly threatened to reject up to 25 percent (or $700 million) of South Carolina's stimulus funds unless a reluctant Republican-dominated legislature sets aside a matching sum of state money to pay down its debt. (He has accepted the rest.) Wearing a crisp white shirt and a blue patterned tie, Sanford looks every inch the polished real-estate mogul he once was—and when he insists that he "can live with" the cash not coming to South Carolina, which opponents say will cost thousands of teachers their jobs, it's hard to imagine him ever losing sleep over something as "common sense" as spending cuts.

But even true believers have bad days, and at this particularly stressful hour, it doesn't take much to set Sanford off. In the halls of the State House, legislators accuse the governor of selling out the poorest South Carolinians to feed his own ambition; outside, his approval ratings have fallen to 40 percent. Asked how this makes him feel, Sanford pauses, then admits to experiencing the "occasional lonely moment." But he still believes, he quickly adds, that there's a "silent majority" of voters who support his stimulus stance; it's just that they're "too busy to make their voices heard." Take the Democratic trial lawyer he "completely convinced" in Mt. Pleasant yesterday, or the "70 or so" people who "showed up last week to be counterprotesters to the protesters." What about them? And what about the "black gentleman" this morning? "I was walking out of a local TV studio, and there he was," says Sanford. "He's a security guy for the building, one of these rent-a-cop kind of guys, older guy. And he walks over, and he grabs my arm, and he says, 'You do what you think is right'." Suddenly, Sanford stops. His eyes are red and wet. He lets out a quick, pained laugh, then looks up at the ceiling. "I'm gonna lose it here," he says finally, turning toward his press secretary. "Got to get my head back in the game." A single tear is running down his right cheek.

Tip O'Neill once said that "all politics is local," and the South Carolina stimulus standoff—the April 3 deadline has been extended indefinitely—is no exception. But it's also something more. For Sanford, 48, whose term-limited tenure as governor ends in 20 months, it's a chance to test the principles that have animated his 15 years in the arena—sustainable spending, smaller government—and perhaps seize a spot on the national stage as the most prominent of what he calls the "true conservatives." For his party, meanwhile, it's a possible turning point. As the nation shifts leftward to accommodate an expanding government, will hands-off economic libertarianism be remembered as a relic of Reagan's '80s? Or will it come roaring back in response? Much of that depends, of course, on whether the president's plan succeeds or fails, and how the public reacts. Like the rest of us, Sanford doesn't know what will happen. But he's already placed his bets—and put his political future on the line.

By now, Mark Sanford is accustomed to life outside the mainstream. Since arriving in Congress in 1995, he has opposed new spending so mulishly that many critics, including some big-government Bushies, consider him an incorrigible ideologue. The effect, it seems, is intentional. No conversation with the governor is complete, for example, without a few mentions of his heart-surgeon father, whose Depression-driven austerity—he'd only spring for a single air conditioner—meant that young Mark and his well-off siblings would spend summer nights sleeping on the floor of their parents' bedroom. Such stories are supposed to show that prudence is part of Sanford's genetic makeup, and given his history, it's difficult to disagree. A "businessman lost in politics"—Sanford earned an MBA from the University of Virginia and spent a few seasons on Wall Street before entering the South Carolina real-estate market—the governor has been known to pick up loose change at campaign rallies, insist that staffers use both sides of an index card and sleep for weeks on the couch of his congressional office. He still gets trims at Supercuts, and rarely forgets to bring a coupon.

Sanford's libertarian politics are an extension of his penny-pinching quirks. He decided to run for Congress after hearing economic doomsayer Jim Davidson warn that America's debt would be its downfall, and even now, he responds to inquiries about his political philosophy by reverently reciting a 122-word quotation often attributed to an obscure 18th-century Scotsman ("a democracy always collapses over loose fiscal policy, always followed by a dictatorship"). Sanford once vetoed 106 pork-barrel projects in a single swoop, then carried a pair of squealing piglets into the statehouse to make his point. Combined with his unorthodoxy on other issues—he opposes foreign interventions such as Kosovo and Iraq, supports environmental conservation and believes that the religious right has been too influential in recent years—this spending obsession girds the governor with an aura of authenticity that's attractive to purists still reeling from Bushonomics, even though his actual record is relatively thin. "He is the candidate Rush Limbaugh and countless others who embrace the cause of shrinking government have been waiting for," writes conservative journalist Reihan Salam: more Barry Goldwater than George W. Bush. A savvy salesman, Sanford clearly recognizes the appeal of immoderation. "What I believe I truly believe," he boasts. "I can't do the flavor-of-the-month approach." So far, he's yet to lose an election.

That said, Sanford's principles aren't helping him weather the economic downturn, which has left South Carolina with the second-worst unemployment rate in the country. Before Congress passed the stimulus bill, the governor proudly questioned the necessity of a federal bailout; afterward, he penned a Wall Street Journal column claiming the plan would "create more problems than it solved"—in direct contrast to the general consensus among economists that government spending is necessary to prevent a steep recession from becoming a depression. At the time, many South Carolina officials, including Republicans such as state House Speaker Bobby Harrell and U.S. Sen. Lindsey Graham, echoed Sanford's opposition to the stimulus package. But they balked when the governor revealed that he was willing to reject millions meant for struggling schools and jails unless the legislature dedicated an identical amount to debt reduction. "Now, I agree with the governor 90 percent of the time," Harrell tells NEWSWEEK. "But it's real shame that he's saying to South Carolina taxpayers, 'I'm not going to let you use this money for K-12 or college or law enforcement, even though you have to pay it back.' It must be philosophical, because it's certainly not practical."

As Sanford holds court at the Fort Mill Rotary Club—the latest in a series of local events designed, he says, to help determine whether he's "out of touch here"—it's obvious that many rank-and-file South Carolinians remain as resistant to the governor's plan as their representatives. The crowd is hardly liberal; nearly every question is prefaced with the phrase "I voted for you twice." But the attendees repeatedly challenge Sanford's judgment. "I understand what you're saying about paying down debt," says Sam White, a self-described fiscal conservative. "But if we end up not getting that money, it doesn't make any sense." "I'm a little lost on the mathematics," adds Guynn Savage, a former town-council member. "Aren't we cutting off our noses to spite our face?" Local school superintendent Keith Callicutt chimes in as well, telling the governor that he'll face a budget cut of $2.5 million to $5 million without an infusion of stimulus cash. It's hardly the sort of scene Sanford wants to show a national reporter, and he soon gets snappish. "I don't think you heard what I said to the last person," he tells one incredulous Rotarian. After the event, Sanford tries to convince his chronicler that he prefers "environments we don't control" to "fake, canned events," even if they're "more left-leaning" or "education-heavy," like this one. But he's immediately interrupted by Rebecca Masters, a former Reagan appointee who has come, as she puts it, to speak truth to power. "Don't take the state down the tubes with you," she says.

Sanford insists that he's not "on a philosophical jihad." In Fort Mill, he calmly frames his plan as a "middle ground" compromise meant to protect the state's finances in case the economy hasn't recovered by the time the stimulus runs out in 2011—"at which point," he adds, "South Carolina will be forced to find a new source of funding to sustain the new level of spending, or to make sharp cuts." It's a reasonable position, and given that Sanford has already agreed to spend more tax dollars this year than ever before—many of them on social-welfare programs—the charge that he's balancing the budget on the backs of the poor doesn't hold up. That said, the state's debt burden isn't nearly as dire as Sanford claims; according to Moody's, South Carolina is one of nine states with a AAA credit rating, and it boasts the lowest debt-per-capita ratio of the bunch. So it's clear that caution isn't the only force at work. During the car ride from Fort Mill to Columbia, Sanford hints at what's really driving him. "We can't spend our way out of a problem that was caused by too much spending," he says. "There's not a huge market for austerity in austere times, but that doesn't take away from the reality of that being where we need to go." It turns out that by backing the powerful state legislature into a corner—do what I want or lose the money—Sanford believes that he can finally reach the promised land; without the $700 million, his thinking goes, the House and Senate will have no choice but to create the leaner, meaner state government he's always dreamed of—even though he admits that "in the near term, clearly South Carolina wouldn't be better off." It's Goldwater's root-canal economics (pain today, efficiency tomorrow) as an elaborate game of chicken. And if Sanford can finally claim, as a side effect, the sort of political victory that's been eluding him for two terms— a résumé boost that would appeal, incidentally, to the kind of conservatives who vote in Republican primaries—then so be it. After all, he's gone in 20 months.

What happens then is anyone's guess, but Sanford's steady schedule of national television hits, op-ed columns and appearances as chairman of the Republican Governors Association has done little to dampen speculation about 2012. Asked at the statehouse whether he's looking forward to returning to business once he leaves office, Sanford is quick with a response. "I am," he says. "OK," says the interviewer. "That's my last one." For a second, Sanford is silent. And then he decides to answer a question that was never asked. "I mean, people always say, 'Are you going to run for president?' and all that stuff … And the truth is, it's sort of this double-jeopardy question, 'cause I always say the same thing: 'I don't know. It's not my intention at this point.' Which is absolutely accurate. And they say, 'Would you positively, absolutely rule it out?' And I say, 'Well, no.' 'Well that means you're contemplating it.' And I say, 'No, well, it's not my aim. It's not where I'm focused.' I just learned long ago in life that the day you got's the day you got. Doors will open and doors will close." The waiting, apparently, is the hardest part.