LOS ANGELES (Reuters) - Dreaming of overnight riches, millions of Americans anxiously awaited Saturday evening’s drawing in the multi-state Powerball lottery, hoping to win a jackpot that has climbed to a record $900 million after a last-minute frenzy of ticket sales.

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The grand prize for Powerball, played in 44 states, Washington, and two U.S. territories, is worth $558 million if a winner chooses an immediate cash payout instead of annual payments over 29 years, according to lottery officials in California, one of the participating states.

The prize, which rises with every drawing that produces a winning series of six numbers held by no ticket buyer, now ranks as the largest jackpot for any lottery in North American history. With almost unimaginable riches at stake, many Americans who normally shun lotteries have joined the long lines of people buying tickets at retail stores across the country.

The drawing will take place Saturday at 10:59 p.m. Eastern. Ticket sales will end at least 59 minutes before the drawing, the Multi-state Lottery Association said on its website.

Dony Elias, 26, an attendant at Stardust Liquor in Los Angeles, said 300 customers picked up tickets for Powerball last night at his store. Elias admitted to buying a ticket for himself, something he said he had never done before.

And like many other players, he has already given some thought to what he would do with the cash.

“I would take a trip to the moon,” he said.

California, the nation’s most populous state, normally sees Powerball sales of $1 million a day, but on Saturday morning sales were a head-spinning $2.8 million an hour, said California Lottery spokesman Mike Bond.

Excitement swirled among ticket buyers despite what some statisticians call mind-boggling odds for the Powerball game - one in 292 million.

Jeffrey Miecznikowski, associate professor of biostatistics at the University at Buffalo, said in an email an American is roughly 25 times more likely to become the next president of the United States than to win at Powerball.

Or to put it another way, the odds are equivalent to flipping a coin 28 times and getting heads every time, he said.

“It doesn’t sound so bad ... but you would be at it for an eternity,” Miecznikowski said.

November was the last time a jackpot winner emerged from Powerball, which is run by the Multi-State Lottery Association.

In the previous drawing on Wednesday night, the jackpot stood at $500 million and nobody won, setting the stage for this latest drawing just before 11 p.m. Eastern on Saturday.

If no one wins again, the jackpot will likely rise to an estimated $1.3 billion by Wednesday, the next scheduled drawing, Bond said. It may cross the $1 billion threshold on Saturday, he said.

The previous record North American jackpot payout for any lottery game was in March 2012, when $656 million was won in the multi-state Mega Millions draw.