Budget vote leader ignored (5)
I believe the answer is:
allot
'budget' is the definition.
(I've seen this before)
'vote leader ignored' is the wordplay.
'vote' becomes 'ballot' (synonyms).
'leader ignored' means to remove the first letter.
'ballot' with its initial letter taken off is 'ALLOT'.
(Other definitions for allot that I've seen before include "Apportion (something to someone)" , "appropriate" , "budget" , "Apportion, share" , "Earmark" .)