Complex sentence: Shelby began his legislative career as a member of the Alabama Senate in 1970, serving until 1978, when he was elected to the House of Representatives from the Tuscaloosa-based 7th District.
Split into simpler sentences: Shelby began his legislative career when elected to the Alabama Senate in 1970. That year he ran for and was elected to the House of Representatives from the Tuscaloosa-based 7th District.