Elected majority is closest to the centre (6)
I believe the answer is:
inmost
'closest to the centre' is the definition.
(the innermost or most central)
'elected majority' is the wordplay.
'elected' becomes 'in'.
'majority' becomes 'most' (most of a group).
'in'+'most'='INMOST'
'is' is the link.
(Other definitions for inmost that I've seen before include "Nearest centre; deepest" , "Furthest inwards, closest to centre" , "Furthest inward" , "Being deepest within the self" , "Deepest within oneself" .)