Fuss unduly about Democrat (2-2)
I believe the answer is:
to-do
'fuss' is the definition.
(I've seen this before)
'unduly about democrat' is the wordplay.
'unduly' becomes 'too' (I've seen this in another clue).
'about' is an insertion indicator.
'democrat' becomes 'd'.
'too' enclosing 'd' is 'TO-DO'.
(Other definitions for to-do that I've seen before include "Quarrel" , "Bustle" , "Fuss or commotion" , "Flap" , "Kerfuffle" .)