Corrupt record separates Democrat from party (7)
I believe the answer is:
deprave
'corrupt' is the definition.
(synonyms)
'record separates democrat from party' is the wordplay.
'record separates democrat' becomes 'dep' (I am not sure about this - if you are sure you should believe this answer much more).
'from' means one lot of letters go next to another.
'party' becomes 'rave' (type of dance party).
'dep'+'rave'='DEPRAVE'
(Other definitions for deprave that I've seen before include "Pervade (anag.)" , "Make corrupt" .)