After a marathon 15-hour final round, an Australian chiropractor turned professional card player has emerged as the new champion of the World Series of Poker. The victory earned him $7.5 million and placed him, for the moment, atop a wave of poker-mania that in the past few years has swept the country.

"How could it not change my life?" 39-year-old Joseph Hachem, his face pasty after a long night and morning in a darkened upstairs card room of Binion's Gambling Hall & Hotel in downtown Las Vegas. "It changes everything."

As Hachem reveled in his victory Saturday morning over a Maryland mortgage banker who seemed astonished even to be in the big game, two guards in suits and ties, brandishing shotguns, watched over a table covered with stacks of cash that represented his winnings -- a pile that a few hours before had been paraded into the card room with theatrical overkill befitting the reality television series that this once obscure event has become.

More than 5,600 players ponied up the $10,000 entry fee and converged on Las Vegas for the weeklong tournament. It was a record turnout.

The numbers reflect an explosion of popularity that has rocketed the game of cowpokes and riverboat card sharks into a modern cultural phenomenon, occasionally making familiar television faces out of otherwise anonymous card players.

The top 560 players finished in the money on a sliding scale that climbed from a thousand dollars or so to a guaranteed $1 million-plus for the nine who made it to the finals, and on to the winner's $7.5 million. The 5,000 losers went home empty-handed, their $10,000 entry fees underwriting the winnings as well as a percentage taken out for administrative costs.