Spade is a regular at the fights, and White’s all over him trying to convince him to come out early for a big party he’s throwing at Mandalay Bay on Friday night featuring Gavin Rossdale and his band, Bush. (Rossdale is another buddy, who just played an acoustic set at the opening of White’s “sick” new beach house in Laguna Beach.) Spade tells him he’s got friends in town, and . . .

Then he calls his agent, Ari Emanuel. Yes, that Ari Emanuel – the guy who’s the basis for the Ari Gold character on HBO’s Entourage and the brother of White House chief of staff Rahm Emanuel. He doesn’t answer, but he texts right back to say he’s at a Lakers game and can’t hear anything.

It’s 6 p.m. on the Thursday before Memorial Day, and Dana White is the king of Las Vegas. In case you don’t already know, White is the president and part owner of the Ultimate Fighting Championship, which means he’s the guy in charge of the biggest organization in mixed martial arts, which may well be the world’s fastest-growing sport. This is about to be one of the craziest weekends of his crazy life; in two days one of the most-hyped fights in the UFC’s history is going down, plus he’s got 125,000 fight junkies coming to town for the UFC’s second fan expo. The ride from his office to his house takes about 12 minutes, and he’s just trying to return a bunch of calls so he can relax and eat pizza with his family before the real chaos begins.

“Are you buddies with Snoop?” I ask. He looks up from his phone and smiles. “I guess we are now.”

White cracks up. He’s got huge shoulders and they shake when he laughs. Then he looks down at his phone again like it’s no big deal. He’s always looking at that phone, even when he’s driving. He’s not the sort of guy who worries about a crash.

“Dana White . . .” it starts. “I’m trying to go to the Rampage Jackson-Evans fight. My people reached out to your people and they said it was sold out. From you to me, me to you. . . . Come on, man, let’s make it official. It’s Snoop!”

He listens to one, kind of shakes his head and laughs, then he gives me that look like he’s glad I’m there because he couldn’t make this stuff up. It’s Snoop Dogg. White hits the speakerphone.

So I’m out in Vegas with Dana White, and we’re driving to his house to eat dinner and he starts checking his messages.

White was born in Manchester, Connecticut, spent his early years in Ware, Massachusetts, and grew up in Vegas with his mother and sister. As a kid, he loved boxing but didn’t always channel his aggression the right way. He was more of a punk than a delinquent and got kicked out of the same Catholic high school twice (the second time for repeatedly kicking a nun’s classroom door shut). He wound up finishing his senior year in Levant, Maine, where his grandparents lived. After graduating, he went back to Vegas for a little while. When his mother, a nurse, moved to Boston, he went to visit her and decided to make the move, too. He got a job as a doorman at the Black Rose in Faneuil Hall, got fired for fighting, took a job paving roads, then worked as a bellman at the Boston Harbor Hotel. The money was good, but he wanted to get back into boxing, so he sought out Peter Welch, a legendary Southie boxer, to become his trainer. At first, Welch didn’t want anything to do with him.

At the end of this month, the UFC will make its Massachusetts debut. That’s when fans paying anywhere from $75 to $600 a ticket will stream into the TD Garden. And that’s when White’s surreal life will come full circle. Back to Boston. Back to his roots in the fight business. And back to the scene of the only fight he ever walked away from.

And at the center of it all is a Southie guy – a 41-year-old former boxer and doorman who has reportedly raked in $200 million and become one of the most powerful men in sports. When I met him, he’d just come back from being a featured speaker at the annual Microsoft CEO Summit along with Warren Buffett and Treasury Secretary Timothy Geithner. But he’s still a fighter at heart, with a look (shaved head, thick neck, top-heavy build) and tongue to match (the f-bomb is his favorite noun, verb, and exclamation).

As far as lives go, it’s a surreal one to follow. Nine years ago, Dana White and mixed martial arts were fringe pipsqueaks in the world of sports. Now the UFC – that franchise with the alpha-dudes brawling in a chain-link octagon – is an empire, and White is its ruler and biggest star. He took this brutal hybrid of boxing and wrestling and judo and other disciplines that’s been called “human cockfighting” and a lot worse, and unseated boxing as the main event in combat. The UFC has shattered records in pay-per-view television. On cable’s Spike TV, 2.2 million people watch its reality show, The Ultimate Fighter, each week; overall, UFC programming reaches 147 countries and territories. Its video game, “UFC: Undisputed 2009,” sold 4 million units worldwide. Two years ago, Forbes magazine estimated the company was worth $1 billion. And it’s only grown since then.

I forgot to mention that there’s a guy from White’s entourage in the back seat, filming the whole thing, and it will go up as a video blog on YouTube for the hundreds of thousands who follow White’s life religiously.

“Slap your [expletive] friends around and tell ’em, ‘Let’s go, we’re going Friday.’ ” White is really giving it to him now. “Show your buddies who the [expletive] movie star is.”

He took his dog for a walk. He’ll never forget that feeling. He was looking over his shoulder, feeling scared and crazy and alone. He wasn’t going to pay them; that much was certain. He went back to his apartment, packed some clothes, left everything else, and got on a flight to Vegas.

A couple weeks later, his phone rang. The caller told him he had till that Sunday to pay them, he says, “or we’ll kill you.”

“The details of what went down were a little cloudy, but the bottom line was: You owe us some money,” he says. “I don’t know why they were [expletive] with me, what the real reason was, but to come after me and bust my balls and try to shake me down was a little weird. They wanted a couple grand from me . . . and I said, ‘I don’t have it.’ They said, ‘Get it from your girlfriend.’ I said, ‘She doesn’t have it, either.’ They said, ‘Well, you better figure it out.’ ”

White eventually gave up on his own boxing dream and devoted himself to being a trainer. Then one day in the summer of 1995, while he was in the middle of teaching a class at the Boston Athletic Club in Southie, two men walked in and told him he had to go outside with them. They were, White says, from the Irish mob.

To pay the bills, White worked with Welch teaching private boxing lessons – the beginning of the boxing-as-fitness craze – to ordinary folks. White couldn’t afford a car, and Welch remembers him riding a mountain bike through the snow, 80 pounds of boxing gear in a hockey bag on his back, to wherever they paid him to go.

UMass-Boston after a few classes. “I went to the University of South Boston, that’s where I went. I learned the fight business there. I became a part of that neighborhood. Obviously there’s a lot of great things I can tell you about Southie, but let’s face it, Southie’s streets – there was some hardcore stuff there.”

They trained in the McDonough Gym, an old boxing dive behind the courthouse in Southie, and White went to school in the ring and on the corners. “People always ask me about going to college,” says White, who dropped out of

“There are guys that come to me all the time and say they want to be a fighter,” Welch says, so he’ll always put them right in the ring and hope taking a couple punches will get them out the door again. “But that wasn’t Dana. From the first blow he took on his chin he proved he had the stuff to stick around the game.”

At the time, MMA was a mess. There were hardly any rules, it was banned in nearly every state, and it had been pulled from pay-per-view. But White believed the sport could take off if he could just get enough people to see it. Four years later, the UFC was $44 million in the hole. There was talk of selling it or folding it. But then two things started to go their way. With revamped rules designed to keep the fighters safer, White began to have success getting MMA sanctioned across the nation and in foreign countries. Time limits and rounds were introduced – UFC bouts are three rounds of five minutes each, with title fights five rounds – and such tactics as head-butting and eye-gouging were outlawed. White likes to point out that there’s never been a death or serious injury in the UFC’s history. “You can’t say that about cheerleading,” he says. Today, MMA fights are sanctioned in 44 states including Massachusetts, which lifted its ban last year. (New York remains one of the holdouts, but debate continues in the state Legislature on whether to legalize it.)

When he went back to Vegas, he worked as a boxing trainer, and then one night he and two high school friends ran into one of the early UFC fighters and asked him to teach them a few things about the sport. The UFC was formed nearly 20 years ago as a series of pay-per-view events created to answer the question of whether a boxer could beat a kung fu specialist, or a wrestler could beat a kickboxer, etc. As the sport evolved, it became clear you needed a mastery of all the different disciplines, what is now known as mixed martial arts, or MMA. White got heavy into the world of MMA – “It’s the answer to the ultimate question: Who’s the baddest dude in the world?” – and became the manager for two of its first stars, Chuck Liddell and Tito Ortiz. In 2001, he learned that the UFC was in financial trouble. White put together a deal with those two high school friends, brothers Frank and Lorenzo Fertitta (who happened to be from the family that owns the Station casinos), who bought the UFC for $2 million, made White president, and gave him 10 percent of the company.

“This” is what happened when he took on another fight everyone said he couldn’t win and did.

“When you talk about stuff like destiny, and [expletive] that happens for a reason, if that isn’t proof, then what is?” he says. “What are the odds that a kid who’s riding a [expletive] mountain bike around Southie, teaching housewives and businessmen and kids how to box, is going to be shaken down to the point where he’s like, ‘[Expletive] this, I’m out of here,’ and leaves?

White has told this story many times. It’s one-sided and seems almost mythical, but no one has challenged him on it, and no one can challenge him on what it did to his life.

The Palace Station is his spot because it’s low-key by Vegas standards. It’s off the Strip, and he can play cards without getting too “smashed,” which is what his entourage calls the fan freakout that follows him everywhere. This drives the entourage crazy, because White stops and talks to every fan, asks where they’re from, listens to what they have to say. Even on a quiet night in a quiet casino, we get stopped a half-dozen times on the short walk to the tables.

“I want to show you my two Ferraris,” he says to me as we get out of the car. They’re parked right out front. They have dust on them; he can’t remember when he left them there.

Now White wants to play some cards. He’s got two hours to kill until he has to go inspect the fan expo, so we hop back in the Range Rover and drive to the Palace Station Casino. As we pull up to the valet, White pulls out a softball-sized wad of hundreds and peels one off. All weekend, I’ll watch as everyone who opens a door or pushes an elevator button gets one or two or three.

His boys, Dana, 9, and Aidan, 8, start having a fight with foam swords in the living room. Dad jumps in with some foam nunchuks and loses to the boys. They both study MMA. His wife, Anne, whom White has known since the eighth grade, is sitting on the couch watching The Hangover with one of White’s uncles. White’s 3-year-old daughter, Savannah, chases their two little dogs. His father stops in, as does his sister-in-law and her daughter. They order some pizzas, and White goes out to meet the delivery guy. A few minutes later, the guy calls back and tells White he gave him way too much money. White tells him it was no mistake; the guy says he can request him in the future.

We get to White’s house and it’s huge, but kind of understated. Then he takes me over to a giant curtain in his living room, hits a button, and reveals a swimming pool straight out of a Disney resort. This thing has cliffs and waterfalls and a grotto, and the second it was done the board at his subdivision told him he needed to tear it down. Every month, he says, they fine him, something like $2,000 or $2,500. “My kids love it,” he says as he hits another button to start the waterfalls. “I’m never [expletive] tearing this thing down.”

But the real turning point for the UFC came in 2005, when White and the Fertitta brothers persuaded Spike TV to carry The Ultimate Fighter by paying production costs. The show took off, the sport exploded, and White thinks this is just the beginning. He’ll tell anyone who will listen that this sport is going to be bigger than the NFL, bigger than soccer, “bigger than anything.” Call him crazy. It won’t be the first time.

White is always as blunt as he is approachable – he shoulder hugs almost everyone he meets, even random fans – but he’s a man used to having near absolute authority. White runs the day-to-day operations of the organization, while Lorenzo Fertitta focuses more on the global brand, with Frank Fertitta having a minimal role. So White’s not just the chief promoter and deal maker; he’s also, with his fighters, judge and jury. And when he’s challenged, the fighter in him comes out. There are lots of people who don’t like MMA, including The New York Times editorial board and the British Medical Association, because they think it’s ultra-violent and should be banned. For the critics, White has a simple answer: “If you don’t like it, don’t watch it.” In the past, he’s clashed with some fighters over their pay (stars can make more than a half million for a fight; newcomers can make as little as $6,000, with another $6,000 if they win), and the amount of control he has over their careers (the UFC has no ranking system; White arranges the fights he thinks the fans want to see), and he won’t hesitate to cut a fighter loose. On the flip side, White is famous for handing out discretionary bonuses for fighters who really throw down (he says he’s gone up to a million for a single fight) and has welcomed back fighters who once feuded with him.

It’s fight night and we’re driving behind the MGM Grand in one of his Ferraris, talking about what happens with a good idea. What happens is it seems obvious in retrospect. People see White with all this money, money no one can believe he has because for the longest time he was the only one who believed in what he was selling. And now that he’s proved he was right, a lot of people with a lot of money have tried to take a piece of the action.

We sit at the table. White is wearing a T-shirt, jeans, and Adidas Gazelles, which is what all the Southie guys wore back when he was one of them. He plays $25,000 in his first hand and wins. He looks at me and says his life is actually pretty simple: He does his job, he spends time with his kids, and he plays cards to relax. It’s just that the stakes are different now. Forty minutes later, Dana White has lost a half-million dollars like it’s nothing. Because it is. He’s won and lost a million plenty of times, he says.

Bobby Moore, a Southie guy who used to be one of White’s clients back at the gym, meets us at a blackjack table and the entourage is all here. It’s actually kind of puny. At events, he’ll have a bodyguard and an assistant or two following him, but for a night out it’s just Moore and Elliott Raymond, the videographer from the car. He’s a photographer who came to town a few years ago to shoot White for a magazine and hit it off.

Mark Cuban and Donald Trump are two of the big-money guys who have sniffed around White’s castle. Trump was involved in a rival group run by the clothing company Affliction. Cuban staged his own MMA fights for his HDNet television channel, and lured one of the UFC’s stars, Randy Couture. But White took them both on, and won. Affliction has folded and Cuban is now a bondholder in the UFC (though his rights are fairly limited). Another group, Strike Force, has a deal with CBS and Showtime to air a few fights a year. As he pulls the Ferrari into the back entrance of the hotel, I ask White why people think he’s an easy target. The question pushes his posture back.

“I’m flattered that we make it look so easy that these guys think they can just go out and do it,” he says. “We’re the ones that built this industry. We’re the ones that started this [expletive]. It’s like me and you sitting in my house watching NASCAR, and say, ‘Look at all the people there. What we should do is go out and steal some of their drivers and start our own thing.’ ”

And now he’s getting animated. “If you come out and say you’re going to compete against me, we’re going to compete.” He turns off the engine and looks me dead in the eye. “We’re going to fight until somebody wins or somebody loses.”

John Morgan, a reporter for the mixed martial arts website mmajunkie.com, says White’s challengers see the money but don’t necessarily understand his relentless commitment to the sport itself. “This is his passion,” Morgan says, “and he feels like they’re riding on his coattails with all the work he’s done to get this sport sanctioned.”

As we make our way up to his massive suite so he can eat and get dressed for the fight, White is still worked up. We sit down at a table, and he looks me down, like a fighter sitting in his corner ready to come out.

“Guess what? Mark Cuban owns HDNet. He owns the [ Dallas Mavericks ]. Donald Trump owns casinos and everything else. CBS is a television network. You know what I do? I’m in the [expletive] fight business. That’s what I do. Every day, all day, 365 days a year, seven days a week, 24 [expletive] hours a day. That’s the business I’m in. You are never gonna [expletive] beat me. Never.”

I know guys like Dana White. I grew up in Southie. And as I look at him across the table, through the haze of Ferraris and wads of cash, the entourages and the waterfalls, the celebrity phone tag and the Irish mob stories, I can still see him. He’s the fighter who knows how good he has it and what he has to do to keep it; he has to keep fighting. Dana White is the only real thing in his surreal life.

///////////////////////////////

The crowd in the MGM Grand arena goes nuts when White enters, his bald head sticking out from his black Tom Ford suit. It takes forever to get to his seat because he stops for so many photos and autographs with fans. We take our seats at the ringside table with the Fertittas and their wives; Anne joins us. White gets on Twitter and starts talking up the fight. (He’s got more than a million followers.)

He puts his phone down – he’s been texting with Shaquille O’Neal, a huge UFC fan who says he wants to fight someday – and starts making the rounds. Tyson and Snoop get the shoulder hugs; he introduces himself to Sam Worthington, who starred in Avatar. He avoids Paris Hilton, who is off to the side playing on her phone and posing for photos, and goes off to chat up Spade, Forest Whitaker, and Wilmer Valderrama.

The undercard fights start and it gets real again. We’re sitting about 2 feet from “the Octagon,” and the sounds are overpowering – the explosion of legs against knees, the grunting exertion of grappling, the thunderclap of bodies hitting canvas. This is pure fighting, man-to-man combat at its most basic. At the other end of our table, NFL stars Reggie Bush and Larry Fitzgerald are wincing. But you can’t look away. It’s epic. Who’s the baddest dude?

By the time the video starts for the main event – the UFC experience involves lots of dramatic video and ear-shattering music – the crowd is going bonkers. Sugar Evans and Rampage Jackson enter the ring in grand fashion, and White is standing up like everyone else, twitching with excitement. The fight starts and Evans immediately staggers Jackson with a punch, sending the two crashing into the cage in front of us. Evans’s wife, a petite woman in a white dress, runs up behind us and yells at her husband.

“Hit him, Rashad!” she screams.

White leans into my ear. “Is your heart beating a thousand miles an hour?” he asks. I tell him it is.

“Me too.”

© Copyright 2010 Globe Newspaper Company.