He wrote about idiot in party spoiling votes — heavens! (10)
I believe the answer is:
dostoevsky
'he wrote about idiot' is the definition.
The definition suggests a singular noun which matches the answer.
'party spoiling votes heavens' is the wordplay.
'party' becomes 'do' (do can informally mean a party).
'spoiling' indicates an anagram.
'heavens' becomes 'sky' (sky is a kind of heavens).
'votes' anagrammed gives 'stoev'.
'do'+'stoev'+'sky'='DOSTOEVSKY'
'in' acts as a link.
Can you help me to learn more?
(Another definition for dostoevsky that I've seen is " Russian author".)