Under Robert’s Rules of Order, a vote that has been taken can be reopened with a motion to reconsider. Only certain members may make it. An early edition says the motion must be made “by a member who voted with the prevailing side,” and it “can be made on the same or succeeding day.”
A losing member cannot reopen the question. Under current rules, the Municipal Research and Services Center explains, rescinding a decision without previous notice “takes a two-thirds vote of votes cast to pass.”