Represent party, or otherwise (7)
I believe the answer is:
portray
'represent' is the definition.
(portraying is a kind of representing)
'party or otherwise' is the wordplay.
'otherwise' is an anagram indicator.
'party'+'or'='partyor'
'partyor' is an anagram of 'PORTRAY'.
(Other definitions for portray that I've seen before include "Depict, present" , "Delineate" , "Play" , "Depict in art" , "Act" .)