Mr Franco said as soon as he realized he had won he started feeling paranoid and put his winning ticket in a safe.
The $768.4 million win ranks behind the $1.586 billion Powerball total shared by winners in California, Florida and Tennessee in January 2016 and the single $1.537 billion Mega Millions jackpot victor from SC last October.
After almost a month of anxiously waiting, a 24-year-old West Allis man has come forward to claim the $768 million Powerball jackpot.
The jackpot - the third-largest in USA history at $768.4 million - has a lump sum cash value of $477 million, according to the Powerball website.
"Good thing my neighbors didn't hear", Franco said.
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Politicians emerged from an emergency meeting pointing fingers at a little-known local Muslim group, National Thowfeek Jamaath. Not much is known about NTJ, which only came to attention previous year when it was blamed for defacing some Buddhist statues.
Franco says he was born in Milwaukee but didn't share where he went to school. It was incredible. My heart started racing, blood pumping. Screamed for about five or ten minutes. I had pretty much felt lucky... it's a weird feeling, not natural at all, ' he said at the press conference. He has set up a legal and financial team to help him.
"I got that paranoia when you think the whole world is after you", he said.
State laws do not allow lottery winners to remain anonymous. The ticket has a cash option of $477 million. "I thought there was somebody behind me every single day".
The jackpot he won on March 27th totaled $768 million. The winning numbers were 16, 20, 37, 44, 62 and the Powerball number 12.
The odds of matching all six balls in the Powerball drawing were 1 in 292.2 million.
Wisconsin Lottery Director Cindy Polzin called the win an "amazing milestone moment" for the state.