DES MOINES, Iowa (AP) — The Mega Millions jackpot has been boosted to $586 million, a jump from the earlier projection but still trailing a $656 million prize last year that was the largest in U.S. history.

Paula Otto, executive director of the Virginia Lottery and Mega Millions' lead director says ticket sales are ahead of projections, one of the primary factors pushing the jackpot higher.

She says the jackpot may be increased one more time on Tuesday morning in advance of the evening drawing.

She says it's expected that between 65 and 75 percent of the 259 million possible number combinations will be in play when the numbers are drawn.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

Strong weekend Mega Millions ticket sales easily could push Tuesday's jackpot above last year's record $656 million prize, a lottery official said.

No ticket matched the six numbers needed to win Friday's $425 million prize. It was raised Saturday to $550 million for Tuesday's drawing — the fourth largest in U.S. history.

Paula Otto, executive director of the Virginia Lottery and Mega Millions' lead director, told the Associated Press on Sunday that sales were up by as much as 20 percent over weekend numbers and were expected to spike on Tuesday, the day of the drawing.

"I think we'll be very close to the record, and maybe even surpass it," Otto said, adding that sales are difficult to predict.

"Lotto players are procrastinators. They tend to buy on the day of the draw," she said.

As of Friday, players had bought enough tickets to cover roughly half of the 259 million possible number combinations, Otto said.

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