Musnad Ahmad 26:701

Waki’ narrated to us, from Isra’il, from Abu Ishaq, from ‘Amr ibn Maymun, from ‘Abdullah, who said: The Messenger of Allah (may Allah bless him and grant him peace) spoke to us in Mina while his back was leaning against a red tent. He said: "Are you not pleased to be a quarter of the people of Paradise?" We said: "Yes." He said: "Are you not pleased to be a third of the people of Paradise?" They said: "Yes." He said: "By Allah, I truly hope that you will be half of the people of Paradise. And I will tell you about that, regarding the scarcity of Muslims among the people on that day; they will not be among the people on that day except like a white hair on a black bull, or a black hair on a white bull. And no one shall enter Paradise except a Muslim soul."