Mr Lawan defeated Ali Ndume in the election conducted by the management of the National Assembly to emerge head of the red chamber.
Mr Lawan who was elected by his colleagues on Tuesday at the red chamber defeated Ali Ndume, another lawmaker from his party, to emerged the leader of the National Assembly.
The secret ballot system was used in 2015 to elect the immediate past leaders of the 8th National Assembly, the system is said to be used in today's election.
A photograph showing the senator-elect with a certificate has been trending online yesterday but the former governor has described it as fake.
Mr Kalu in a statement said his decision to step down is in the interest of the ruling party and the country at large.
The former governor also said his stay at the red chamber was that of sadness and happiness.
Mr Goje withdrew from the race after meeting with President Muhammadu Buhari on Thursday at the presidential villa, Abuja.
Several efforts to oust him from his position often met brick walls with the Senate President atimes outsmarting his opponents.
The decision of the opposition members may further boast the chances of Femi Gbajabiamila to succeed Yakubu Dogara, the outgoing speaker who is no longer interested in the position.
Mr Dogara stated this in reaction to online reports wherein he is said to be interested in retaining his seat at the lower chamber of the National Assembly.