Counting as influential (7)
I believe the answer is:
telling
This clue is a double definition.
'counting' is the first definition.
(I've seen this before)
'influential' is the second definition.
(I've seen this before)
'as' acts as a link.
(Other definitions for telling that I've seen before include "Giving an order" , "briefing" , "Powerful - effective" , "Counting" , "relation" .)