Democrat anger is dreadful (4)
I believe the answer is:
dire
'dreadful' is the definition.
('dire' can be a synonym of 'dreadful')
'democrat anger' is the wordplay.
'democrat' becomes 'd'.
'anger' becomes 'ire' ('ire' can be a synonym of 'anger'**).
'd'+'ire'='DIRE'
'is' is the link.
(Other definitions for dire that I've seen before include "Really awful kind of ride" , "Portentous" , "Very serious indeed" , "Cataclysmic" , "Ride around can be calamitous" .)