One of the also-rans is realist?
I believe the answer is:
no-hoper
'one of the also-rans' is the definition.
(person or horse unlikely to win a race)
I don't understand how the rest of the clue works.
Can you help me to learn more?
(Other definitions for no-hoper that I've seen before include "One with little prospect of success" , "Or phone (anag.)" , "Useless person" , "One unlikely to succeed" , "One with little chance of success?" .)