Support promotion thus taking clear raise (9)
I believe the answer is:
adherence
'support' is the definition.
(I know that adherence is a type of support)
'promotion thus taking clear raise' is the wordplay.
'promotion' becomes 'ad' (short for advert).
'thus' becomes 'hence' (synonyms).
'taking' is an insertion indicator.
'clear' means to remove the middle letters (I've seen 'cleared' mean this (the inside letters are cleared out)).
'raise' with its centre removed is 're'.
'hence' going around 're' is 'herence'.
'ad'+'herence'='ADHERENCE'
(Other definitions for adherence that I've seen before include "devotion" , "Sticking together" , "loyalty" .)