One whom people don't admit is not a favourite (8)

I believe the answer is:

outsider

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'not a favourite' is the definition.
(I've seen this before)

I cannot understand how the remainder of the clue works.

(Other definitions for outsider that I've seen before include "non-member required" , "Not a member of the group" , "One unlikely to win" , "Someone excluded" , "Someone not accepted by society" .)

I've seen this clue in The Globe and Mail.

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