When Emily Leach stopped by Liquor & Tobacco, a convenience store in Mountain View, before Friday’s drawing for the lottery’s Mega Millions jackpot — then worth $290 million — she was already a kind of celebrated figure at the store after winning $1 million on a lottery ticket she bought there in January.

Her recent good fortune allowed her to perform random acts of generosity for strangers, so it wasn’t completely out of character when Leach offered $100 to one of the men waiting in line behind her as she turned in an armload of Scratchers cards. During that transaction, she either unintentionally handed the stranger a Mega Millions ticket she had just bought, or made him the lucky recipient of some truly astounding generosity.

Just how generous became apparent Sunday. That’s when Leach learned a lottery ticket purchased while she was in line had hit for $260,000. The still unidentified man she gave the $100 returned to the store Saturday to say he had the ticket, and according to Leach, to claim that her good luck had rubbed off on him.

There was just one problem: Leach insists she never intended to buy the lottery ticket for him, and she wants it back.

“That’s my ticket,” Leach said. “He knows it’s my ticket. I feel like I’m going to come off as a huge, huge bitch if I say, ‘You need to give me my ticket back.’ ”

‘What are the odds?’

But that is what she’s saying. The state lottery commission’s security department is investigating, and may use the store’s surveillance video to sort out the situation.

“She said she had the ticket in her hand and maybe it got mixed in with the money she gave this person,” said Alex Traverso, a spokesman for the lottery commission. “They’re going to look at the video and see if she’s the one actually buying the ticket. If no one else is in the picture, that puts things firmly in her favor.”

The ticket holder still had not come forward to lottery officials as of Monday.

“It’s a miracle for one person to hit twice at the same store,” Leach said. “What are the odds of someone like me hitting it once in January, and again less than three months later?”

According to the lottery commission, the odds of her winning $1 million in January were 1 in 1.2 million; because of the number of players, she had only a 1 in 3.9 million chance to win Friday. The combined odds against winning twice in three months are simply off the charts.

She has faced even more daunting odds. A nurse at the Veterans Affairs hospital in Palo Alto, she was diagnosed with a pancreatic tumor at a time when she had no health insurance. “I went into the hospital on a Sunday three years ago, and I woke up two months later,” she said. “I had been in a coma, and the doctors told my mother to plan my funeral.”

After getting threatening calls from bill collectors, Leach’s sudden prosperity became both blessing and curse. She was able to pay off more than $300,000 in medical bills.

But she also turned into a soft touch. “There have been plenty of negatives,” she said. “Everybody knows everything about me, and everybody has their hand out.”

Before Friday’s drawing in the Mega Millions lottery, Leach stopped by the store that has brought her so much luck — good and bad — to buy more lottery tickets. The man in line behind her to buy beer seemed to know her life story.

“He said, ‘You’re so lucky,’ and then he started crying and said his gas tank was on empty, and he really needed help. So I gave him a hundred-dollar bill. I told him, ‘Don’t buy any more beer. Do something good for yourself.’ “

Leach said that with all the Scratchers tickets in her hands, as she fumbled in her purse for the money — trying not to show how much she was carrying with her — she pulled out the hundred-dollar bill and a lottery ticket together. What remains in dispute is whether she intended to hand both pieces of paper to a man she had never met.

Surveillance video

On Sunday, Leach went back to Liquor & Tobacco and was told a ticket had hit for $259,269. She says she was told by the clerk that the man whose beers she bought had returned Saturday, and credited her with buying the ticket for him. “That never happened,” Leach insisted. “If you look on the surveillance video, in the time frame the ticket was bought, I am the only person that paid for anything in that store.”

Lottery business was booming at the store Monday, where owner Young Pham said he planned to turn over the tape to investigators in the next few days. Leach said if the ticket holder does “what I think is the right thing,” she would continue to be a generous person. “I think he should give me the ticket back,” she said. “If he were to do that, I certainly wouldn’t take it and just walk away.”

Contact Bruce Newman at 408-920-5004. Follow him at Twitter.com/brucenewmantwit.