Complex sentence: Although conservative Republicans were not pleased that Rockefeller was picked, most of them voted for his confirmation; nevertheless, a minority block (including Barry Goldwater, Jesse Helms and Trent Lott) voted against him.
Split into simpler sentences: Although conservative Republicans were not pleased that Rockefeller was picked, most of them voted for his confirmation. However, some, including Barry Goldwater, Jesse Helms, Trent Lott, and others voted against him.