Government leader in luck backing spin (10)
I believe the answer is:
chancellor
'government leader' is the definition.
(I've seen this before)
'luck backing spin' is the wordplay.
'luck' becomes 'chance' (synonyms).
'backing' is a reversal indicator.
'spin' becomes 'roll'.
'roll' backwards is 'llor'.
'chance'+'llor'='CHANCELLOR'
'in' is the link.
(Other definitions for chancellor that I've seen before include "Government leader" , "Head of government" , "Govt. finance minister" , "Titular university head" , "chief minister" .)