Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) says that the Messenger of Allah (peace and blessings be upon him) said: "When there are three, one of them should lead them in prayer, and the one most entitled to lead is the one who has read the most of the Qur'an."
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 5287