Cop collects millions in support of member (7)
I believe the answer is:
armrest
'support of member' is the definition.
'armrest' can be an answer for 'support' (armrest is a kind of support). I'm not sure about the 'of member' bit.
'cop collects millions in' is the wordplay.
'cop' becomes 'arrest' (synonyms).
'collects millions' becomes 'm' (I am not sure about this - if you are sure you should believe this answer much more).
'in' means one lot of letters goes inside another.
'arrest' going around 'm' is 'ARMREST'.
Can you help me to learn more?
(Other definitions for armrest that I've seen before include "Padded side to a chair" , "Part of a carver chair" , "Support for one member" , "Chair or car seat part" , "support of chairperson?" .)