NEW YORK (REUTERS) - A winning ticket for an estimated US$636 million (S$800 million) Mega Millions jackpot, approaching the biggest US lottery prize ever, was sold in San Jose, California, a lottery official said on Tuesday night.

There was no immediate word about who won, but the winning ticket was bought at a retail location in San Jose, California, according to Mr Alex Traverso, a lottery official in the western US state.

The winning numbers were: 8, 14, 17, 20, 39, and 7, according to the lottery's website, Megamillions.com.

"There could be more, that's the only one we know right now," Mr Traverso said.

If the winner chooses to take the lump sum cash option, instead of payments over 30 years, the jackpot would be US$341 million, the lottery said.

The prize swelled after a spike in sales ahead of Tuesday night's drawing. As much as 70 per cent of the tickets are typically bought on the day of the drawing, said Ms Paula Otto, Virginia's lottery director, who heads the multi-state Mega Millions game.

At a corner grocery store on Manhattan's Upper East Side, ticket buyers lined up for a chance to strike it rich, and shared their dream shopping lists.

"I would give at least half of it to my church," said Keith Boyd, pastor at the nearby Trinity Baptist Church, who bought 20 tickets to give away as gifts while keeping one for himself. "It would be a way to bless others."

Mr Syed Waheed, a 37-year-old immigrant from Afghanistan who bought a single ticket, said he would use the fortune to bring his entire family to the United States.

Ticket buying reached a fever pitch over the weekend, with 20 per cent more chances sold than expected, Ms Otto said.

The surge of spending pushed the prize closer to the record US jackpot of US$656 million, won in March 2012 in a Mega Millions drawing.

"We're awfully close, just US$20 million. We're right on it," Ms Otto said on Tuesday.

Totals would be updated again after the drawing, she said.

By Tuesday's drawing, players should have bought enough tickets to cover 65 per cent to 75 per cent of the 259 million possible number combinations to strike it rich, she added.

"You don't know you have a winner unless it's 100 per cent covered, though," she said.

Although at least one ticket matched the exact combination of numbers that appear on six randomly selected lottery balls, if no one claims the prize, it will keep ballooning until the next drawing on Friday, when the numbers were projected to jump to a US$950 million jackpot with a US$509 million cash option.

"We've never had a jackpot this high the week before Christmas," said Ms Otto.

"You like to see winners and you like to see big jackpots. I leave it in the hands of the bouncing balls."