Ricardo Thomas / The Detroit News

Sen. Barack Obama addresses the NAACP delegates. All the Democratic candidates were warmly received, but Obama, an African-American appearing before an African-American crowd in the nation's most African-American city, drew by far the loudest applause. He said that while government cannot guarantee success, it is "a betrayal of our ideals" for people to be held back from opportunity because of their skin color or their economic class.