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How's this for madness: This month's NCAA men's basketball tournament figures to be the biggest sports-betting event in world history. An estimated $9.2 billion will be traded through a combination of legal betting, office pools and illegal sportsbooks operating overseas.

That's a slight increase from the $9 billion spent last year. In fact, for all of the attention that March Madness generates as a cultural sports event, its related sports-betting activity might be an even bigger occasion.

But what's truly stunning about those numbers isn't the $9.2 billion figure alone. It's the fact that just a fraction of that betting -- a mere $262 million, according to the American Gaming Association -- will be done the legal way, through Nevada sports books. The rest of it will be done through illegal means, which for most casual gamblers means absolutely nothing.

Some big fish might find themselves in the crosshairs of the federal government. But the average American gambler will face virtually no consequence for skirting U.S. gambling laws and placing a friendly wager or two.

In a report detailing the estimated action during March Madness, the American Gaming Association dubbed sports gambling "the new national pastime." In other words, the scale of sports betting as an illegal recreational activity is rivaled only by marijuana and jaywalking.

In this one regard, March Madness trumps even the Super Bowl. This year's Super Bowl 50 generated about $132 million in legal bets, and another $4.1 billion in illegal wagers. That's less than half the volume March Madness will see.

Geoff Freeman, president and CEO of the American Gaming Association, says it's a sign of changing attitudes regarding sports betting in America. In fact, he credits some of the success of March Madness to the betting frenzy that goes on around the game.

"Americans' passion for betting fuels the unmatched popularity of March Madness," Freeman said. "Betting increasingly drives sports fans -- and even casual observers -- to invest in the tournament, offering further evidence that sports betting is the new national pastime.

"It's time for a fresh, rational approach to sports betting that reflects this reality."

Gambling Facts

AGA also cites the heavy participation in bracket tournaments as an indicator of March Madness's addictive qualities. According to its estimates, more than 70 million brackets will be filled out for this month's college basketball tournament.

Bloomberg cautions that bracket pools and bracket-style contests may not comprise a huge chunk of the gambling pie -- it estimated last year that about 16 percent of all illegal betting is done through brackets, with the rest of that money going to Vegas-style wagers on spreads, over/unders, prop and parlay bets.

But the brackets could play a critical role in building an engaged audience -- one that knows the ecstasy of picking and underdog and getting it right. In some ways, brackets could help prime basketball fans for illegal Vegas-style betting, building a familiarity and comfort with college basketball and its gambling sideshow.

One thing is clear: Outlawing sports gambling has done nothing to curb activity. Instead, the federal government looks hapless and ineffective, having no credible means of regulating gambling or punishing offenders.

Unless you play for a college or professional team, sports-betting regulations are starting to look like blue laws, equivalent to the Kansas state law that prohibits the shooting of rabbits from motorboats. (It's true.)

That's a bad look for the government, but it's great for fans who want to put a buck on Hampton upsetting Virginia. You'll probably lose, but maybe you'll get lucky.

Either way, you won't be getting in trouble. Happy gambling!

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