The president said this in his acceptance speech, Wednesday, at the Peoples Democratic Party (PDP) 2014 National Convention at the Eagle Square, Abuja.
Nigeria is undergoing great changes at this time, and also experiencing great challenges; so, political parties must rise above the fray, to provide hope and clear direction, to propel the development of our country. My brothers and sisters, the PDP as a party has delivered on its promise. In the last decade, it has seen to the largest expansion of the middle class in Africa.

Certainly, our Party has a rich history of enduring legacies. Our political opponents shall assail us with the fury of their desperation to win power. They will use every means – intimidation, false accusations, hostile media and more. Do not descend to their level. We must stay focused on the mission at hand – to secure Nigeria’s future.
Let me emphasise again, that nobody’s political ambition is worth the blood of any Nigerian. We must eschew violence, even in the face of the most outrageous acts of desperation.

For those who defected from the PDP, I enjoin you to tell the truth in your campaigns. Many of the developments in your States were initiated by the PDP. So be honest with the voters and give credit where it is due.

Distinguished Delegates, ladies and gentlemen, I stand before you as your humble servant, to accept your nomination as the Presidential candidate of our great Party, the PDP.
Having placed great faith in me and chosen me as your candidate, I assure you, that I am truly honoured tonight, to lead another electoral contest.
This will be a campaign, and an election, that will serve to consolidate our successes.
I will give my all.
I will not let you down.
I will not fail the PDP.
I will not fail you.

Source: http://www.vanguardngr.com/2014/12/nobodys-political-ambition-worth-blood-nigerian-jonathan/