As soon as libertarian presidential candidate Gary Johnson rolls up to the restaurant in Scottsdale, Ariz., his driver, Tom Mahon, jumps out of his seat and hands me a Sharpie.

Michael Friberg for TIME Johnson bodysurfs the crowd at a recent town-hall meeting in Salt Lake City

As soon as libertarian presidential candidate Gary Johnson rolls up to the restaurant in Scottsdale, Ariz., his driver, Tom Mahon, jumps out of his seat and hands me a Sharpie. Mahon says that as a libertarian, he wants me to sign the campaign vehicle wherever I like and write whatever I like. So just below Johnson’s head, I write, “I didn’t do this,” and draw an arrow toward the mustache, beard and marijuana cigarette already on Johnson’s face. Being a true libertarian means driving around in a van with graffiti on your face.

Johnson isn’t one of those incapable, extremist, wacky, millionaire third-party candidates. He is extremist: he wants to abolish the IRS, legalize marijuana and allow the private sector to create competing currencies. Sure, he’s a little wacky: he’s finished 75 triathlons, climbed Mount Everest eight weeks after breaking his leg in a skiing accident and crashed while paragliding. And yeah, he’s a millionaire: in 1999 he got $10 million for a handyman business he started his junior year of college and built into a 1,000-employee construction firm.

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But he’s capable. As a Republican, he won two terms as governor of New Mexico with no prior political experience, eliminating the deficit and creating a surplus before leaving office in 2003 with high approval ratings—which he recovered after dipping 30 points when he talked about drug legalization. “Ron Paul is a social conservative,” he says. “I’m not. Ron Paul would talk about legalizing marijuana, but he’s never smoked marijuana.”

For months, as Johnson ran in the Republican presidential primary, the GOP ignored him as best it could, hoping he’d just go away. Then he did, leaving the Republicans to join the Libertarians. When I ran into him at the GOP convention in Tampa, Johnson looked like a man far removed from his former party, blocks from the convention center, standing on a street corner in front of a Hooters doing interviews.

The GOP isn’t ignoring him anymore. Now that Johnson is threatening to siphon votes from Mitt Romney in close elections in Colorado and Nevada (he’s also on the ballot in 46 other states and Washington, D.C.), Republicans are doing whatever they can to limit his appeal. Michigan party officials kept him off the ballot because he filed his paperwork three minutes late. In Pennsylvania, the GOP hired a private detective who went to canvassers’ homes and flashed his old FBI badge before questioning the signatures they collected, a lawyer for Johnson’s campaign alleged. The state GOP and the investigator denied doing anything improper. (On Oct. 10 a judge decided that Johnson will be on the Pennsylvania ballot.) The experience has left Johnson, 59, alienated from some of his old comrades—which, it turns out, he doesn’t mind at all. “Going to Republican events, as I did a zillion times, I listened to Republican candidates do their spiel. I cringed at a lot of what they said, whether it was abortion, the terrorist threat, the homophobia, the ‘illegal immigrant is the source of all our problems’—man, that stuff made me crazy. The kook element of the Libertarians gets up, and I don’t cringe.”

Johnson lacks the passion of fellow Libertarian Ron Paul, but he projects far more humanity. Born in Minot, N.D., Johnson was a George McGovern–supporting anti–Vietnam War pot smoker who went to high school and college in New Mexico and started his empire as a door-to-door handyman. He still has a Midwesterner’s accent and decency: he says things like “holy cow” and “Katie, bar the door.” His running mate, Jim Gray, a former California Superior Court judge whom Johnson met at a drug-legalization conference, says Johnson often seems to lack ego. “He said to me, ‘If, during the campaign, you have different ideas than I do, feel free to say that publicly.'”

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Johnson is running a tiny operation, flying commercial and carrying his luggage to avoid bag-checking fees. He’s spent a lot of his limited cash (he had $29,173 left at the end of September) suing to get on the ballot and doesn’t have a lot left to run his campaign, much less buy TV ads. “Fifty people a day are calling our office, offering to do anything for free. And we don’t have the resources to tap into them,” he says.

Not that anyone could really organize Johnson’s “coalition” anyway. After our dinner, a couple hundred people gather on a lawn at Arizona State University, which is pretty impressive, since it’s 100°F. The crowd: tatted-up students with marijuana-legalization shirts, young parents with little kids wearing Ron Paul shirts, crusty old men applauding wildly when warm-up speakers mention economist and austerity guru Friedrich Hayek, Constitution freaks with the Preamble on their shirts, guys selling cards with bits of silver who want to get us back to hard currency, a few Latinos who feel strongly about the Dream Act, antiwar activists in peace T-shirts. Libertarianism is the smallest big tent in the world.

Johnson isn’t the strongest speaker. After being introduced by Barry Goldwater Jr.—who recently endorsed Mitt Romney—Johnson opens with “So” and then talks about how even a homeless person could solve the country’s problems, but, unlike a homeless person, he is qualified. He says many things that no winning presidential politician has ever said: “I didn’t create one single new job in New Mexico. The private sector creates jobs!” followed shortly by a boast about how many liberty torches the ACLU has awarded him. It feels less like he’s running for President than for student president of the University of Chicago.

As he leaves the stage and heads to the airport so he can fly to the University of Nevada at Las Vegas, he reflects on his chances. “I’m planning to exceed expectations,” he says with a smile. “Which are zero.”

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