The 52-year-old and her husband, who live in Upton, Wirral, are both massive Reds who met on the Kop nearly 28 years ago.
Karen, who bought her ticket online, has already decided how she’ll spend her cash prize.
“I’m going to use some of the winnings as spends while on holiday with my mum in Las Vegas,” she said.
“She hasn’t been too well, so I can’t think of a better way to spend the money. I still can’t believe I won, especially with it being the first game.”
The LFC Foundation Lottery was launched on August 12 ahead of Liverpool’s 4-0 victory over West Ham United at Anfield.