The party made this known through a statement by its National Publicity Secretary, Lanre Issa-Onilu, on Wednesday.
The statement added that under the leadership of Adams Oshiomhole as National Chairman, the party has made significant progress.
"This is the example President Buhari has shown by ensuring that we had a presidential election in this country without seeking to award himself any advantage over his opponents.
"The President has the instruments to use under him, but he rather subjected himself to the rules of the contest. If the President did not expect the party to manipulate his own election, why should anyone else expect that from the party?"
On attacks against Oshiomhole's leadership, Onilu said, "We should remember that our President was elected in 2015 with over 15 million votes as against the PDP's 13 million plus. There was about 2.5 million votes difference.
"Under Oshiomhole, we have over 15 million votes as against PDP's 11 million plus. There you have nearly four million votes difference. So for the Presidential election, our party has improved significantly on the result of 2015.
"The situation was expectedly different at the state level. The state players have the foremost responsibility to win elections in their states.
"What we can do at the national level is to provide the necessary support. The support starts from conducting transparent primaries that ensure the party produces popular candidates.
"Of course, certain state players in our party expected business as usual where other players are subjugated for them so that their wishes are imposed on other APC members in their states.
"This we could not do and I dont think we need to apologise for doing the right thing. By now, the states that failed to follow the party's directives are the ones that may be regretting.
"We have examples of Governors who are true progressives who worked with the NWC to ensure things were done right. Look at Kaduna, Plateau, Niger, Kano, Nasarawa, Katsina, Jigawa, Borno, Yobe, etc.
"The Governors and leaders of APC in these states worked according to the rules in conjunction with the NWC and we all can see that the sweetest victory is the one achieved under a free and fair engagement with the opposition."