DENVER – Barack Obama stepped triumphantly into history Wednesday night, the first black American to win a major party presidential nomination, as thousands of Democrats transformed their convention hall into a joyful, shouting celebration.
 
							
			
								
			            
            
				
			
            
            DENVER – Barack Obama stepped triumphantly into history Wednesday night, the first black American to win a major party presidential nomination, as thousands of Democrats transformed their convention hall into a joyful, shouting celebration.