Musnad Ahmad 1:17

'Affan narrated to us, he said: Abu 'Awanah narrated to us, from Dawud ibn 'Abdullah al-Awdi, from Humayd ibn 'Abd al-Rahman, he said: The Messenger of Allah (peace and blessings of Allah be upon him) passed away while Abu Bakr was in a part of Medina. He said: So he came and uncovered his face and kissed him, and said: "May my father and mother be ransomed for you, how pleasant you are, alive and dead! Muhammad (peace and blessings of Allah be upon him) has died, by the Lord of the Kaaba." Then he mentioned the hadith. He said: So Abu Bakr and 'Umar set off, leading one another until they came to them. Abu Bakr spoke, and he did not leave anything that was revealed regarding the Ansar, nor anything the Messenger of Allah (peace and blessings of Allah be upon him) mentioned regarding their status, except that he mentioned it. And he said: "You certainly know that the Messenger of Allah (peace and blessings of Allah be upon him) said: 'If the people traveled through a valley, and the Ansar traveled through a valley, I would travel through the valley of the Ansar.'" "And you certainly know, O Sa'd, that the Messenger of Allah (peace and blessings of Allah be upon him) said, while you were sitting: 'Quraysh are the rulers of this affair; the righteous among the people follow their righteous, and the wicked among them follow their wicked.'" He said: So Sa'd said to him: "You have spoken the truth. We are the ministers, and you are the emirs."