By Barbara Goldberg
(Reuters) - A last-minute ticket buying frenzy a week before Christmas inflated Tuesday's Mega Millions jackpot to $636 million, threatening to become the biggest U.S. lottery prize in history, a game official said.
The prize swelled after a spike in sales early on Tuesday before the 11:00 p.m. EST (0400 GMT, December 18) drawing, said Paula Otto, Virginia's lottery director, who heads the multi-state Mega Millions game.
If the winner chooses to take the lump sum cash option, instead of payments over 30 years, the jackpot would be $341 million, Otto said.
As much as 70 percent of the tickets is typically bought on the day of the drawing, she said.
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."
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 percent more chances sold than expected, Otto said.
The surge of spending pushed the prize closer to the record U.S. jackpot of $656 million, won in March 2012 in a Mega Millions drawing.
"We're awfully close, just $20 million. We're right on it," Otto said on Tuesday.
Totals will not be updated again until after the drawing, she said, so it will be Wednesday before lottery officials know if the record is surpassed.
The more tickets sold, the better the chance that someone will match one of the 259 million possible number combinations that could land a jackpot. By Tuesday's drawing, players will have bought enough tickets to cover 65 percent to 75 percent of the possible number combinations to strike it rich, Otto said.
"You don't know you have a winner unless it's 100 percent covered, though," she said.
If no one picks the exact combination of numbers that appear on six randomly selected lottery balls, the prize will keep ballooning until the next drawing on Friday, when the numbers were projected to jump to a $950 million jackpot with a $509 million cash option.
"We've never had a jackpot this high the week before Christmas," said Otto.
"You like to see winners and you like to see big jackpots. I leave it in the hands of the bouncing balls," Otto added.
(Additional reporting by Elizabeth Dilts. Editing by Andre Grenon)