Force politician to get involved in raising some money (5)
I believe the answer is:
impel
'force' is the definition.
(synonyms)
'politician to get involved in raising some money' is the wordplay.
'politician' becomes 'mp' (Member of Parliament).
'to get involved in' is an insertion indicator.
'raising' says the letters should be written backwards.
'some money' becomes 'lei' (I've seen this before).
'lei' back-to-front is 'iel'.
'mp' put into 'iel' is 'IMPEL'.
(Other definitions for impel that I've seen before include "Spur on" , "Constrain" , "Send or drive forward" , "Hold together" , "Urge or drive to do something" .)