In favour of melody that could make a lot of money (7)
I believe the answer is:
fortune
'a lot of money' is the definition.
(I've seen this before)
'in favour of melody' is the wordplay.
'in favour of' becomes 'for' (being for a particular cause).
'melody' becomes 'tune' (synonyms).
'for'+'tune'='FORTUNE'
'that could make' acts as a link.
(Other definitions for fortune that I've seen before include "large sum of money" , "Big bucks - fate" , "Providence" , "Fate, destiny" , "Great accumulation of wealth" .)