A seat occupied by Liberal — is this a record? (5)
I believe the answer is:
album
'this a record?' is the definition.
(I've seen this before)
'a seat occupied by liberal' is the wordplay.
'seat' becomes 'bum' (synonyms).
'occupied by' is an insertion indicator.
'liberal' becomes 'l' (abbreviation).
'a'+'bum'='abum'
'abum' placed around 'l' is 'ALBUM'.
'is' acts as a link.
(Other definitions for album that I've seen before include "Cuttings book" , "Book of blank pages for collectables, memorabilia etc." , "LP, CD; blank book" , "Book for stamps/photos" , "Music record or photo book" .)