An election judge and election clerk shall challenge, or other qualified voter in the city may challenge a person attempting to vote if the challenger has good reason to believe that the challenged person is not qualified to vote. All challenges shall be made in writing explaining the reason for the challenge. Before voting, a challenged person shall take an oath and sign an affidavit provided by the City Clerk attesting to the fact he meets all the qualifications of a voter; that he is not disqualified, and that he has not already voted at the same election. He shall also state the place from which he came immediately before living in the city and the length of time of his residence in the former place. After the challenged person has taken the oath and signed the affidavit, the person may vote. If the challenged person refuses to take the oath or sign the affidavit, the person may not vote.