Kemp was a professional quarterback for 13 years. He played briefly in the National Football League and the Canadian Football League. His true gridiron career pinnacle point though was in the American Football League, where he served as captain of both the San Diego Chargers and Buffalo Bills and earned the AFL Most Valuable Player award in 1965 after leading the Bills to a second consecutive championship.

Kemp, a distinguished quarterback who played primarily for the Buffalo Bills, enjoyed a notable NFL career from 1957 to 1969. Over his 13 seasons, Kemp threw for 40,559 yards and 236 touchdowns. He was instrumental in leading the Bills to AFL championships in 1964 and 1965, earning AFL Most Valuable Player honors in 1965. Kemp's leadership on the field and ability to execute crucial plays solidified his reputation as a top quarterback. After his playing career, he continued to make an impact as a politician and advocate, further enhancing his legacy beyond football.