§ Md. Election Law § 10-305(untitled)

(a) If there is a vacancy in the polling place staff during voting hours: (1) the local board may fill the vacancy with a substitute election judge who has been recruited and trained; or (2) an election judge who is present at the polling place may fill the position of the absent election judge by appointing a person registered with the same party affiliation as the absent election judge. (b) If a substitute election judge is appointed under subsection (a) of this section: (1) either the election director, the election director’s designee, or the election judge making the substitute appointment shall administer the oath required under § 10-204 of this title; and (2) a chief election judge shall document any change in the polling place staff in the records of the polling place.