Musnad Ahmad 907:0

Narrated Jabir ibn Samurah as-Suwa'i: I heard the Messenger of Allah (ﷺ) say: "This religion will continue to remain mighty, prevailing over those who oppose it, until twelve Caliphs have passed, all of them from Quraysh." Then he said something that I did not understand, so I asked my father: "What did he say?" My father said: "He said: 'All of them will be from Quraysh.'"