Denver, CO - August 28, 2008 -- Former Vice President Al Gore, the 2000 Democratic nominee for President of the United States speaks on day 4 of the 2008 Democratic National Convention at INVESCO Field at Mile High Stadium in Denver, Colorado on Thursday, August 28, 2008..Credit: Ron Sachs - CNP.(RESTRICTION: NO New York or New Jersey Newspapers or newspapers within a 75 mile radius of New York City)