Candidate not backing away, this writer’s choice in the end (7)
I believe the answer is:
nominee
'candidate' is the definition.
(I know that candidate can be written as nominee)
'not backing away this writer's choice in the end' is the wordplay.
'not backing' becomes 'nom' (I can't justify this - if you can you should believe this answer much more).
'away' is an anagram indicator (letters move away from their original places).
'this writer' becomes 'I' (the person writing the crossword).
'end' indicates one should take the final letters.
The final letters of 'choice in the' are 'ene'.
'i'+'ene'='iene'
'iene' anagrammed gives 'inee'.
'nom'+'inee'='NOMINEE'
Can you help me to learn more?
(Other definitions for nominee that I've seen before include "Person standing for office" , "Candidate for office" , "Chosen person" , "somebody put up" , "One named as candidate" .)