One making his voice heard via ballot box -- nothing odd about that (4)
I believe the answer is:
alto
'one making his voice heard via ballot box nothing odd about that' is the definition.
'alto' can be an answer for 'one making his voice heard' (type of singing voice). I am unsure of the remainder of the definition.
'ballot box nothing odd about that' is the wordplay.
'nothing odd about that' indicates alternate letters (letters in odd-numbered positions are removed).
'ballot'+'box'='ballotbox'
The alternating letters of 'ballotbox' are 'ALTO'.
Can you help me to learn more?
(Other definitions for alto that I've seen before include "One who sings" , "Woman's singing voice" , "A singing voice or pitch" , "Voice part" , "Lowest female singing voice" .)