Painful to accept Conservative account (5)
I believe the answer is:
score
'account' is the definition.
('score' can be a synonym of 'account')
'painful to accept conservative' is the wordplay.
'painful' becomes 'sore' ('sore' can be a synonym of 'painful').
'to accept' indicates putting letters inside.
'conservative' becomes 'c' (abbreviation commonly used in UK politics).
'sore' going around 'c' is 'SCORE'.
(Other definitions for score that I've seen before include "Group of 20" , "Number of runs" , "Keep count" , "Mark; orchestrate" , "Hit - music" .)