He also worked with Sen. Russ Feingold, D-Wis., to eliminate gifts of travel on corporate jets by lobbyists to members of Congress.

In December 2006, President George W. Bush signed into law the Democratic Republic of the Congo Relief, Security and Democracy Promotion Act of 2006, marking the first enactment of federal legislation primarily sponsored by Obama.

As a U.S. senator, Obama held assignments on various committees, including Foreign Relations, Homeland Security and Governmental Affairs, and Veterans' Affairs.

On June 3, 2008, Obama captured the delegates necessary to become the first black nominee for president of the United States.

On his website, Obama said: "I'm asking you to believe. Not just in my ability to bring about real change in Washington ... I'm asking you to believe in yours."