Praise a Conservative allegation (7)
I believe the answer is:
acclaim
'praise' is the definition.
(thesaurus)
'a conservative allegation' is the wordplay.
'conservative' becomes 'c' (abbreviation commonly used in UK politics).
'allegation' becomes 'claim' (I've seen this before).
'a'+'c'+'claim'='ACCLAIM'
(Other definitions for acclaim that I've seen before include "Declare" , "Great public praise" , "Credit" , "Plaudits" , "Cheer" .)