A supporter welcomes almost affluent continental (7)
I believe the answer is:
african
'continental' is the definition.
(I've seen this before)
'a supporter welcomes almost affluent' is the wordplay.
'supporter' becomes 'fan' (fan is a kind of supporter).
'welcomes' indicates putting letters inside (in sense of 'invites in').
'almost' means to remove the last letter (most of the word but not all of it).
'affluent' becomes 'rich' ('rich' can be similar in meaning to 'affluent').
'rich' with its final letter taken off is 'ric'.
'fan' enclosing 'ric' is 'frican'.
'a'+'frican'='AFRICAN'
(Other definitions for african that I've seen before include "Black" , "From a certain continent" , "Person from, eg, Congo" , "Person from Kenya, say" , "Zimbabwean, perhaps" .)