Vote against bolshie tweeter (7)
I believe the answer is:
redpoll
'tweeter' is the definition.
Although both the answer and definition are singular nouns, I can't see how they can define each other.
'vote against bolshie' is the wordplay.
'vote' becomes 'poll' (polling is a kind of voting).
'against' is a charade indicator (letters next to each other).
'bolshie' becomes 'red' (bolshevik - red can informally mean communist).
'poll' after 'red' is 'REDPOLL'.
Can you help me to learn more?
(Other definitions for redpoll that I've seen before include "Flyer" , "cow" , "finch" , "Bird" .)