Mr Isaac Osei has been the second aspirant to concede defeat to Nana Akufo-Addo in the party’s historic presidential election held on Saturday August 7, 2010.

Prof. Frimpong Boateng was the first to concede defeat on Joy FM. A third contender, Alan Kyerematen is yet to speak himself, however the head of his campaign, Kwabena Agyei Agyapong, has conceded already and says Alan will cap it at the Efua Sutherland's Children's Park when all the contenders and party leaders are to gather for the official declaration from the Electoral Commission.

Kwabena Agyapong called the provisional results so far as an "emphatic and profuse mandate" as well as "very clear victory for Nana."

In an interview with Joy News, Mr Isaac Osei admitted the “quite obvious” after more than half of the results from 228 constituencies had been collated, declaring that Nana Akufo-Addo, a lead contender in the presidential slot, was in for a “tremendous and massive victory”.

He said the result shows a great endorsement from the delegates “and I think Akufo-Addo is the winner”.

He made a clarion call to other contenders to concede defeat and stressed he accepts the verdict without any question.

“What is important is that NPP has been through a competitive election and we have a winner who I believe deserves the victory that he has been given. So Isaac Osei probably did not do as well as some people might have thought but that is the verdict of the people of our party and I accept that verdict without any question at all.”

He promised an unflinching support to Nana Addo’s bid to become Ghana’s president in the 2012 general elections. He also asked his supporters to support Nana Addo.

He said he has made frantic efforts to call Nana Addo to personally congratulate him but was not successful; he however sent a text message to him to that effect.

Mr Osei noted that Nana had a groundswell support which was “very difficult for everyone to penetrate” largely because he (Nana) was well marketed to the people during the 2008 elections that saw him lost to the incumbent President, Prof. Atta Mills, by a slim margin.

Mr Isaac Osei who is also the Member of Parliament for Subin constituency in the Ashanti Region lost to Nana Akufo-Addo even in his own background. He had 138 votes while Nana Addo polled 298 votes in that constituency, and described that as disappointing.