Bird making socialist vote (7)
I believe the answer is:
redpoll
'bird' is the definition.
(redpoll is a kind of bird)
'socialist vote' is the wordplay.
'socialist' becomes 'red' (red can informally mean a socialist).
'vote' becomes 'poll' (polling is a kind of voting).
'red'+'poll'='REDPOLL'
'making' acts as a link.
(Other definitions for redpoll that I've seen before include "Flyer" , "Bird" , "cow" , "finch" .)