Musnad Ahmad 626:2

Ya'la ibn 'Ubayd Abu Yusuf narrated to us, Isma'il narrated to us, from Qays, from al-Mughirah ibn Shu'bah, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "A group of my Ummah will continue to be dominant over the people until the command of Allah comes to them, and they are dominant."