I heard the Messenger of Allah ﷺ say, "This religion will continue to stand firm until there have been twelve caliphs over you, all of whom the ummah will unite upon."Then I heard the Prophet ﷺ say something I could not make out, so I asked my father, "What is he saying?"He replied, "All of them will be from Quraysh."
حدثنا عمرو بن عثمان حدثنا مروان بن معاوية عن إسمعيل يعني ابن أبي خالد عن أبيه
سمعت رسول الله ﷺ يقول لا يزال هذا الدين قائما حتى يكون عليكم اثنا عشر خليفة كلهم تجتمع عليه الأمة فسمعت كلاما من النبي ﷺ لم أفهمه قلت لأبي ما يقول قال كلهم من قريش
Its chain of transmission is daif. Bayhaqi transmitted it in Dalail Nubuwwah 6/519, 520 from the hadith of Abu Dawud, through it. Marwan bin Muawiya and Ismail bin Abu Khalid both used ambiguous transmission wording (an'ana). The hadith that follows makes it unnecessary.