Complex sentence: The success of the song in America is credited to American radio personality Jim Connors, who helped promote the song on the radio despite its length, and helped it to stay on the charts for 16 weeks.
Split into simpler sentences: The success of the song in America is credited to American radio personality, Jim Connors. He helped promote the song on the radio, despite its length, and helped it to stay on the charts for 16 weeks.