Sen. Barack Obama, right, makes a surprise appearance with his running mate, Sen. Joe Biden, Wednesday at the Democratic National Convention in Denver.

Sen. Barack Obama, right, makes a surprise appearance with his running mate, Sen. Joe Biden, Wednesday at the Democratic National Convention in Denver.

Sen. Barack Obama completed an improbable and historic journey Wednesday when he was nominated by acclamation as the Democratic candidate for president, becoming the first black man to lead a major political party into a general election campaign.

Sen. Joe Biden also accepted the vice presidential nomination, and former President Bill Clinton gave Obama an unqualified endorsement.