As revealed by Ilana, a candidate is a person who is capable of replacing Jacob as the protector of The Island and, in particular, The Source. The exact criteria of what constitutes a candidate has not been revealed, however, they seem to have a special protected status among The Others, as evinced by Dogan's insistence that the remaining candidates remain inside The Temple where they will be safe. Ilana notes that there are only six candidates remaining in the episode "Ab Aeterno", however, since that revelation two candidates, Sayid and either Sun or Jin, have died, bringing the total number of remaining candidates to three. They are Hugo "Hurley" Reyes, James "Sawyer" Ford and Jack Shephard.