27 To be elected to the treaty body, members must obtain both the largest number of votes and an absolute majority of votes from representatives of States parties present and voting at the meeting. If the first round does not yield enough members to fill all the vacant positions, the rules of procedure provide for additional rounds of voting until all vacancies are filled. Occasionally, a position becomes vacant before the end of the four-year term, for example because a member has resigned or passed away. Depending on the wording of the treaty, such a vacancy is filled either through the appointment of a new member by the State party that nominated the original member or through a by-election. Generally, treaties provide that the State party that nominated the original member may appoint a replacement from among its nationals to serve the remainder of the term. However, in the case of the Committee on the Elimination of Racial Discrimination, the Committee on the Elimination of Discrimination against Women, the Committee on the Rights of the Child and the Committee on Migrant Workers, the treaty body must approve the appointment before it is formalized. In the case of the Committee against Torture, the Subcommittee on Prevention of Torture and the Committee on Enforced Disappearances, the States parties must approve the appointment. In the case of the Committee on Economic, Social and Cultural Rights, there is also a formal procedure for the election of a candidate from the regional group, who is usually from the State of the initial member. When the treaty requires the appointment to be approved by the States parties, the approval is considered to be obtained automatically unless at least half the States parties reject the candidate within six weeks of the notice from the Secretary-General informing them of the proposed appointment. The Convention on the Rights of Persons with Disabilities does not set out an approval mechanism, although it requires the proposed candidate to possess the qualifications and meet the requirements for members as set out in the Convention. The International Covenant on Civil and Political Rights requires such vacancies to be filled through a by-election at an extraordinary meeting of States parties, unless the term of office of the member being replaced expires within six months of the formal notification by the Secretary-General of the vacancy. The SecretaryGeneral organizes the by-election in the same way as a regular election. If the term has less than six months to run, no action is necessary. For more information on nominations and elections, see: United Nations, Human Rights Treaty Bodies and Election of Treaty Body Members: A Guide for United Nations Delegates Based in New York (2013), available from www.ohchr.org.