According to the Merriam-Webster Dictionary candidate is "one that aspires to or is nominated or qualified for an office, membership, or award", for example, a candidate for mayor (like Homer Simpson in this pic).
Candidate derives from Latin candidatus, meaning "one aspiring to an office," but originally "white-robed," (past participle of candidare "to make white or bright") because candidates wore white togues in ancient Rome. Candidacy (American) and candidature (British) are words derived from candidate.
Candid, from candidum ("white") has got the same root as candidate, but at the same time as candle, incandescent, incendiary or incense.
So, just for playing with words, Real Madrid footballers could be candidates, etymologically speaking, as their kit is completely white. The point now is "candidates for what, for being beaten 5-0?" Come on, Real Madrid supporters, don't get angry, just kidding ;-)