While still with the group, Thornton had some American chart success as featured vocalist on the Le Click hit "Tonight is the Night", which reached number 68 on the "Billboard" Hot 100. The song was included on the U.S. version of La Bouche's debut album, peaking at number 28 on the "Billboard" 200. It was certified platinum by the RIAA and sold over 8 million copies worldwide. Thornton provided guest vocals on a lot of dance projects on single releases such as on Orange Blue's "If You Wanna Be (My Only)", Comic's "I Surrender to Your Love", 100%'s "Power of the Light", Trance-Vision's "Take Me 2 Heaven 2 Nite" and Men Behind's "How Can I".