LYNN – There is only one thing that won’t change in Erica St. John’s life if she manages to defy the one in 175 million odds against winning tonight’s Mega Millions Lottery drawing.”My relationship with my family – that’s what is most important,” St. John said Thursday as she purchased a Mega Millions ticket at Tedeschi market on Lewis Street.Everything will change in Pat Marino’s life if he wins, beginning with a new house and a new car.Like Tedeschi regulars Jay Surette and St. John, Marino usually avoids long odds Lottery games like Mega Millions and Power Ball in favor of the continuous play opportunities afforded by Keno and Daily Race.But, as Lottery players in Massachusetts and 11 other states can attest, not taking a chance at winning $270 million is tough to do.”Last I checked, we were selling 3,000 tickets a minute,” said Lottery spokesman Dan Rosenfeld.Tonight’s Mega Millions drawing is the fifth largest jackpot in the game’s history. The prize hit $390 million on March 6, 2007 with two winning tickets sold in New Jersey and Georgia.The winning five numbers and winning Mega ball number will be drawn on Channel 5 at 11:24 p.m. The winner gets the choice of taking the prize money in equal annual installments over 20 years or accepting a $164.3 million pre-tax cash option.Surette said he will retire from his maintenance worker job and donate a lot of money to charity if he wins.”I’ll take good care of my kids and my 2-year-old grandson.”All three players said they are ready to weather the possible pitfalls associated with mega wealth.”When you get a new car, they give you an owner’s manual. They don’t give you one for your life if you win Mega Millions,” Marino said.