Main's best-known role was Ma Kettle in the Ma and Pa Kettle film series. She had renewed her contract with MGM for another seven years, which continued until the mid-1950s, when the studio loaned her to Universal Pictures to play Ma Kettle for the first time in "The Egg and I" (1947), starring Claudette Colbert and Fred MacMurray. Main played opposite Percy Kilbride as Pa Kettle, and was nominated for an Academy Award for Best Actress in a Supporting Role for her performance in the film.