Complex sentence: Behind the scenes, Nixon staff lobbied for delegates from "favorite son" candidates, resulting, in the backing of Senator Howard Baker of Tennessee, and his 28 delegates amassed, as well as those 58 delegates belonging to Senator Charles Percy of Illinois.
Split into simpler sentences: Behind the scenes, Nixon workers lobbied for delegates from "favorite son" candidates. As a result, Nixon received the backing of Senator Howard Baker of Tennessee, and the 28 delegates he had amassed, as well as the 58 delegates belonging to Senator Charles Percy of Illinois.