A Berliner's affirmative vote, one opposed by people of Paris (4)

I believe the answer is:

ajax

'one opposed by people of paris' is the definition.
(in Greek myth, Ajax fought Trojans including Paris)

'a berliner's affirmative vote' is the wordplay.
'berliner's affirmative' becomes 'ja' ('yes' in German).
'vote' becomes 'x' (how votes are marked).
'a'+'ja'+'x'='AJAX'

(Other definitions for ajax that I've seen before include "Greek warrior (Iliad)" , "Cleaner" , "Old war hero" , "eleven from the Netherlands" , "classic war hero" .)

I've seen this clue in The Guardian.

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