Tinubu made this known in Lagos, while address the stakeholders of the party in the state.
The Leader further reprimanded former President Olusegun Obasanjo for his frequent attacks on the government of Buhari.
Tinubu stated that the criticism of the former president are worthless as they would not debar Nigerians from voting for Buhari.
He also added that the defection of some of the members of the party to other parties would not affect the reelection bid of the President.
“Our president, President Muhammadu Buhari has done well, he deserves another term, and we will support him to win because he is our man.
“Forget about Obasanjo’s letter and his frequent attacks on our president, he cannot stop the president because Nigerians would re-elect him.
“Obasanjo has spent his own time; he should leave Buhari alone and face his business because he cannot tell us who to vote for.
“He is part of some of the challenges we are facing in the country today, because he did not lay the right foundation when he was president,” he said.
Tinubu said that the results of the Kogi,Katsina and Bauchi bye elections, in which the APC was victorious, were a precursor to the pattern of the general elections.
“I congratulate the winners in the election and their victory is proof that our party is getting more popular by the day.
“Those who want to defect can defect, that is their problem. APC remains unshaken and these people will know the reality in the election,” he said.
Tinubu also used that opportunity to applaud the National Chairman of the Party Mr. Adams Oshiomhole, adding that the party faithful were satisfied with his achievement so far.
He said that the direct primary system was good for democracy, and the party would adopt it to conduct its primaries.
He urged the members to mobilse others to obtain their Permanent Voter Cards as that was necessary for victory in 2019.