An ordinary Muslim is eligible to lead a nikah ceremony. Nikah in fact is the announcement of a man and woman in the public and witnesses that they are going to accept each other as spouses. Reciting the verse of the Quran is to remember God and to ask for His blessings and addressing the people (khutba e Nikah) is nothing but availing an opportunity to tell good things to the people who gather at that occasion.
Ghamidi sahib writes in his book, “Meezan”
Marriage is an open declaration of a contract by a man and a woman to live permanently as husband and wife. It is declared in the presence of people through a responsible personality with great solemnity and gravity after he delivers a sermon to counsel and guide them.