One pursuing partisan struggles (8)
I believe the answer is:
aspirant
'one pursuing' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'partisan struggles' is the wordplay.
'struggles' indicates anagramming the letters.
'partisan' is an anagram of 'ASPIRANT'.
Can you help me to learn more?
(Other definitions for aspirant that I've seen before include "Hopeful, wannabe" , "expressing high ambition?" , "One with ambition" , "Candidate; one with a desire to succeed" , "pretender" .)