One who has little backing, but he hasn't been taken in (8)
I believe the answer is:
outsider
'one who has little backing' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'he hasn't been taken in' is the wordplay.
I cannot really understand how this works, but
'he' could be 'sid' and 'sid' is found in the answer.
The remaining letters 'outer' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
'but' is the link.
Can you help me to learn more?
(Other definitions for outsider that I've seen before include "Someone not accepted by society" , "One not part of group" , "Competitor rated as unlikely to succeed" , "Unfancied competitor" , "One who doesn't belong (or isn't fancied)" .)