"With profound gratitude and great humility, I accept your nomination for Presidency of the United States."
Obama was more fiery than in the past, as he sought to make working class Americans believe he would fight for them and he is of them.
"We are more compassionate than a government that lets veterans sleep on our streets and families slide into poverty; that sits on its hands while a major American city drowns before our eyes. Tonight, I say to the American people, to Democrats and Republicans and Independents across this great land - enough!"
Criticized in the past for giving speeches long on oratory and short on policy specifics, Obama mentioned at least 35 specific policy proposals.
"Let me spell out exactly what that change would mean if I am President. Change means a tax code that doesn't reward the lobbyists who wrote it, but the American workers and small businesses who deserve it."
And he took on his Republican rival aggressively, making 21 references to McCain by name.
"Senator McCain likes to talk about judgment, but really, what does it say about your judgment when you think George Bush has been right more than ninety percent of the time? I don't know about you, but I'm not ready to take a ten percent chance on change," he said, evoking laughter from the crowd.
The attacks may have struck some as too negative.
"If John McCain wants to have a debate about who has the temperament, and judgment, to serve as the next commander-in-chief, that's a debate I'm ready to have."
But Obama's attacks on MccCain on foreign policy may have also been a way to try to project toughness on national security.
"John McCain likes to say that he'll follow Bin Laden to the gates of hell - but he won't even go to the cave where he lives."
The speech also was a way for Obama to introduce himself as someone with working class roots.
"I think about my mom, who raised my sister and me on her own while she worked and earned her degree. I don't know what kind of lives John McCain thinks celebrities lead, but this has been mine. "
And then after he concluded, a dramatic ending as Obama was joined by his family and his running mate.
The speech also included some Biblical allusions and 54 uses of the word America or American.