State support for golf channel (6)
I believe the answer is:
gutter
'channel' is the definition.
(I know that gutter is a type of channel)
'state support for golf' is the wordplay.
'state' becomes 'utter' (both can mean to say).
'support for' is a charade indicator (letters next to each other) (in a down clue, some letters 'support' others).
'golf' becomes 'g' (phonetic alphabet: alpha, bravo, charlie etc.).
'utter' put after 'g' is 'GUTTER'.
(Other definitions for gutter that I've seen before include "Channel to carry away rainwater" , "Rain channel; (flame) start to die" , "Where snipe can be found" , "Street channel for carrying off rainwater" , "Channel at the side of a street" .)