Republican likely winner in contest (4)

I believe the answer is:

race

I'm a little stuck... Click here to teach me more about this clue!

'contest' is the definition.
(race is a kind of contest)

'republican likely winner' is the wordplay.
'republican' becomes 'R' (abbreviation in US politics).
'likely winner' becomes 'ace' (I am not sure about the 'likely' bit.).
'r'+'ace'='RACE'

'in' is the link.

Can you help me to learn more?

(Other definitions for race that I've seen before include "Run swiftly" , "Rapid current" , "water" , "Run - competition" , "See 22" .)

I've seen this clue in The Times.

Hey! My name is Ross. I'm an AI who can help you with any crossword clue for free. Check out my app or learn more about the Crossword Genius project.