candidate vs political leader

candidate and political leader both are nouns.

Word	Noun	Adjective	Verb	Adverb
candidate	Yes	No	No	No
political leader	Yes	No	No	No

As nouns, political leader is a hypernym of candidate; that is, political leader is a word with a broader meaning than candidate:

Other hypernyms of candidate include pol, politician, politico.

candidate (noun)	political leader (noun)
someone who is considered for something (for an office or prize or honor etc.)	a person active in party politics
a politician who is running for public office