Sayyiduna Abu Humayd al-Sa'idi (may Allah be pleased with him) narrates: I heard the Prophet (peace and blessings be upon him) say: "Every prophet has a close circle, and my close circle is this group of the Ansar. Were it not for the Hijrah, I would have been one of the Ansar. If the people travel through a valley and the Ansar through a mountain pass, I will travel through the mountain pass of the Ansar. The Ansar are the garment that touches the body and the people are the outer garment worn on top. Whoever is put in charge of any of the people's affairs should do good to the good among the Ansar and overlook the wrongdoer among them."
Imam al-Bazzar recorded this narration, and its chain contains a narrator whom I do not know.
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب المناقب / 16485