Mega Millions jackpot grows to an estimated $640 million

By Alli Knothe and Peter Schworm, Globe Correspondent and Globe Staff

Tonight’s Mega Millions lottery jackpot has grown to an estimated $640 million, according to the Massachusetts Lottery.

The jackpot had already broken the record Thursday for the largest lottery prize in history.

The new estimate, which was $100 million higher than Thursday’s, was announced this morning after officials from participating states spoke with each other and assessed the volume of ticket sales. Paul Sternburg, executive director of the Massachusetts Lottery, said the estimate was conservative and could rise even higher after all the ticket sales are tallied tonight.

Over the past three days, nearly $9 million in tickets have been sold in Massachusetts. As of noon, the total for the day was approaching $3 million. But the busiest time was expected to be between 5 p.m. and 7 p.m., Sternburg said. “The sales figures are flying,” he said.

He estimated that the day’s sales could eventually total $10 million to $15 million. Tickets for the game are $1.

If a winner is not drawn tonight, the jackpot will climb to nearly $975 million. He said that would be a problem for lottery agency billboards in other states that will not have enough digits to display the jackpot if it goes over $1 billion.

He said he would be surprised if there’s no winner tonight, but “anything is possible.”

The winner of tonight’s drawing, if there is one, can elect to receive a lump sum of $462 million. Otherwise, the prize will be paid out over 26 years.

Laura Paquette, a cashier at Marlboro Market on Massachusetts Avenue near Marlborough Street, said the store was busy during her afternoon shift with people buying lottery tickets.

“Every second customer is buying Mega Millions tickets,” she said. Paquette, who has been working at the store for about a year, said many people bought 20 or more tickets at a time.

It was the busiest Rita Patil had ever seen the Corner Market in Chelsea, where she has been working for eight years.

“One guy bought $200” worth of tickets, said Patil. She couldn’t guess at the number of people who had come in so far, but said people were returning several times to buy tickets. “Some people go home and come back,” she said.

The odds of winning in the lottery game, which is offered in 42 states and the Virgin Islands and District of Columbia, are 1 in 176 million.

The drawing will be held tonight at 11 p.m. Tickets can be purchased up until 10:45 p.m., according to the Massachusetts Lottery website.