Obvious victory for former PM (7)
I believe the answer is:
baldwin
'former pm' is the definition.
(Stanley Baldwin, former UK prime minister)
'obvious victory' is the wordplay.
'obvious' becomes 'bald'.
'victory' becomes 'win' (a win is a victory).
'bald'+'win'='BALDWIN'
'for' is the link.
(Other definitions for baldwin that I've seen before include "Former PM" , "British PM three times between WWI and WWII" , "Prime minister" , "Medieval monarch - black American writer - British premier" , "British statesman" .)