Bringer of good luck for member at racecourse (6)
I believe the answer is:
mascot
'bringer of good luck' is the definition.
(I've seen this before)
'member at racecourse' is the wordplay.
'member' becomes 'm'.
'at' means one lot of letters go next to another.
'racecourse' becomes 'ascot' (I've seen this before).
'm'+'ascot'='MASCOT'
'for' is the link.
(Other definitions for mascot that I've seen before include "Symbolic figure, for a team say" , "Team's good-luck bringer" , "Symbolic lucky figure" , "Lucky talisman" , "Something considered to bring good luck" .)