Lofton was born in Kingfisher, Oklahoma. He attended Kingfisher High School, where he was a standout player for the Kingfisher Yellowjackets high school football team. A three-year letterman and starter, he also played fullback. He led his team in tackles with 168 during his senior year and 505 over his career, helping lead his team to the 3A state championship in 2003 and helping them advance to the semifinals in 2004. Curtis was coached during high school, including his junior year where he led Kingfisher to its first state championship, by Rick Vancleave, Stan Blundell, Mark Redwine, Larry Hart, and Doug Jech. He rushed for 12 touchdowns as a senior. Lofton was a Parade first team All-American (2004), The Oklahoman All-State (2004), first-team coaches All-state 2004 and also nominated for the March of Dimes Oklahoma Headliners Banquet as one of the top scholar-athletes in the state of Oklahoma.