Beer with a politician? That's chancy (8)
I believe the answer is:
aleatory
'chancy' is the definition.
(I've seen this in another clue)
'beer with a politician?' is the wordplay.
'beer' becomes 'ale' (type of beer).
'with' is a charade indicator (letters next to each other).
'politician?' becomes 'Tory' (term for a Conservative Party politician).
'ale'+'a'+'tory'='ALEATORY'
'that's' is the link.
(Other definitions for aleatory that I've seen before include "depending on chance" , "dependent on chance" .)