nominee vs politician

nominee and politician both are nouns.

Word	Noun	Adjective	Verb	Adverb
nominee	Yes	No	No	No
politician	Yes	No	No	No

As nouns, politician is a hypernym of nominee; that is, politician is a word with a broader meaning than nominee:

Other hypernyms of nominee include pol, political leader, politico.

nominee (noun)	politician (noun)
a politician who is running for public office	a person active in party politics
	a leader engaged in civil administration
	a schemer who tries to gain advantage in an organization in sly or underhanded ways