Deadlock that is about politician and idiot (7)
I believe the answer is:
impasse
'deadlock' is the definition.
(synonyms)
'that is about politician and idiot' is the wordplay.
'that is' becomes 'ie' (synonyms).
'about' means one lot of letters goes inside another.
'politician' becomes 'mp' (Member of Parliament).
'and' means one lot of letters go next to another.
'idiot' becomes 'ass' (I've seen this before).
'mp'+'ass'='mpass'
'ie' placed around 'mpass' is 'IMPASSE'.
(Other definitions for impasse that I've seen before include "deadlock results" , "Unpromising situation" , "block" , "nothing can be done" , "Maybe gridlock" .)