Barack Hussein Obama (born August 4, 1961) is the junior United States Senator from Illinois. The U.S. Senate Historical Office lists him as the fifth African American Senator in U.S. history and the only African American currently serving in the U.S. Senate. He served in the Illinois Senate from 1997 to 2004, and launched his U.S. Senate campaign in 2003. Midway through campaigning as the Democratic nominee, Obama delivered the keynote address at the 2004 Democratic National Convention and became a nationally known political figure..