SAN FRANCISCO - JULY 31: Presumed Democratic presidental candidate Sen. Barack Obama (D-IL) speaks via satellite TV to members of the American Federation of State, County and Municipal Employees (AFSCME) at the Moscone Center July 31, 2008 in San Francisco, California. The AFSCME held their bi-annual meeting to elect their international vice presidents, amend resolutions and to confirm their endorsement for Democratic Presidential Nominee Barack Obama.