Sympathetic, perhaps, to congressional organisation distancing itself from Ross (9)
I believe the answer is:
congenial
'sympathetic' is the definition.
(associated in meaning)
I don't understand the remainder of the clue.
Can you help me to learn more?
(Other definitions for congenial that I've seen before include "Pleasant and agreeable" , "relaxing" , "Having similar interests" , "Suited to one's taste" , "Harmonious and friendly" .)