Oath a Democrat supports, say (4)
I believe the answer is:
egad
'oath' is the definition.
(archaic oath or exclamation)
'a democrat supports say' is the wordplay.
'democrat' becomes 'd'.
'supports' says to put letters next to each other (bottom letters provide a support for the top ones).
'say' becomes 'eg' (both can mean 'for example').
'a'+'d'='ad'
'ad' after 'eg' is 'EGAD'.
(Other definitions for egad that I've seen before include "Oath sworn" , "Mild oath (archaic)" , "Forgotten curse" , "Mild oath - aged (anag)" , "Archaic expression of anger, surprise, etc" .)