While there may not be any state-approved casinos in the state of Texas, if you want a date with Lady Luck, there are many choices.

But there's only one with as much charm -- or as many lucky charms -- as bingo. It's a multi-million dollar business to the state and its legal.

"Between all of our halls, we have 25 local charities and the last quarter, each one of those charities made $18,000 apiece," said Kris Keller, of I-35 Bingo.

That's how bingo is legal. But it's also how this form of gambling attracts people like Doris Johnson.

"We don't like clubs. We don't drink, we don't smoke, so we like to go play bingo," she said.

And like most of the folks who pack the hall nightly, there's an art to the luck. Charms abound: lucky seats, lucky tables.

"One of our games is the Lucky Pig and it comes with a pig and they use that as their luck," said Peggy Stradley, of I-35 Bingo.

The fact is that unlike racetrack betting or poker, there's no real skill involved -- just lots of social interaction.

Among the charities who benefit from the bingo call at that hall are Alamo Heights Little League, the Lions Club, Save Baby and the Knights of Columbus.

In 2011, charitable bingo won $533 million in prizes. The charities in Texas got $29 million.