Part of stage raised by some minor party (5)
I believe the answer is:
apron
'part of stage' is the definition.
(I've seen this before)
'raised by some minor party' is the wordplay.
'raised by' is a reversal indicator.
'some' indicates a hidden word (some of the parts of the word are used).
'norpa' is hidden within 'minor party'.
'norpa' back-to-front is 'APRON'.
(Other definitions for apron that I've seen before include "Type of stage; pinny" , "Put on to protect" , "Pinny -part of the fairway leading onto the green" , "that's used by Oliver!?" , "skirt" .)