Following the 2011 Egyptian revolution, the Muslim Brotherhood in Egypt became one of the main forces contending for political power in Egypt against the Supreme Council of the Armed Forces (SCAF) and other established centers of the former Hosni Mubarak regime. In June 2012 Parliament instituted the Constituent Assembly of Egypt, tasked to prepare a new constitution to be approved in a referendum. The constitution was supported by 63.8% of voters in the referendum, held in December of that year.