Protest about renegade party member (8)
I believe the answer is:
democrat
'party member' is the definition.
(thesaurus)
'protest about renegade' is the wordplay.
'protest' becomes 'demo' (I've seen this before).
'about' becomes 'c' (abbreviation for 'circa'**).
'renegade' becomes 'rat' (I've seen this before).
'demo'+'c'+'rat'='DEMOCRAT'
(Other definitions for democrat that I've seen before include "US politician" , "One who believes in government by the whole people" , "Person who believes in government by and for the people" , "Believer in popular government" , "Cleveland?" .)