Barack Hussein Obama (born August 4, 1961) is the junior United States Senator from Illinois and a member of the Democratic Party. 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.

Born to a black Kenyan father and a white American mother, Obama grew up in culturally diverse surroundings. He spent most of his childhood in the majority-minority U.S. state of Hawaii and lived for four years in Indonesia. A graduate of Columbia University and Harvard Law School, Obama worked as a community organizer, university lecturer, and civil rights lawyer before running for public office. He served in the Illinois Senate from 1997 to 2004, launching his campaign for U.S. Senate in 2003.

Obama delivered the keynote address at the 2004 Democratic National Convention while still an Illinois state legislator. He went on to win election to the U.S. Senate in November 2004 with a landslide 70% of the vote in an election year marked by Republican gains. As a member of the Democratic minority in the 109th Congress, Obama co-sponsored the enactment of conventional weapons control and transparency legislation, and made official trips to Eastern Europe, the Middle East, and Africa.

He is among the Democratic Party's leading candidates for nomination in the 2008 U.S. presidential election. Since announcing his candidacy in February 2007, Obama has emphasized ending the Iraq War and implementing universal health care as campaign themes. He married in 1992 and has two daughters. He has authored two bestselling books: a memoir of his youth titled Dreams from My Father, and The Audacity of Hope, a personal commentary on U.S. politics.