FACTBOX: Barack Obama, 44th U.S. president

(Reuters) - Barack Obama was sworn in as the 44th president of the United States at noon on Tuesday.

Here are some biographical facts about the first African-American to hold the nation's highest office.

Age: 47

Birthdate: August 4, 1961

Birthplace: Honolulu, Hawaii

Education: Columbia University; Harvard Law School

Wife: Michelle Robinson Obama

Children: Daughters Malia, 10, and Sasha, 7

Religious affiliation: United Church of Christ

Party: Democrat

Family: Barack Obama was born to a Kenyan father and a white American mother. His father, Barack Obama Sr., married his mother, Ann Dunham, while studying at the University of Hawaii. The couple separated two years after Obama was born. His father ultimately returned to Kenya, where he became a noted economist. He died in a car accident in 1982.

Obama's mother's second marriage was to an Indonesian man named Lolo Soetoro. The family moved to Indonesia and Obama remained there until he was 10 when he moved back to Hawaii and lived with his grandparents while studying on a scholarship at the elite Punahou Academy.

He has seven half brothers and sisters in Kenya from his father's other marriages, and a half-sister, Maya Soetoro-Ng, from his mother's second marriage.

Career: After finishing college in 1983, Obama worked for a New York financial consultancy and a consumer organization. He landed a job in Chicago in 1985 as an organizer for Developing Communities Project, a church-based group seeking to improve living conditions in poor neighborhoods.

Three years later, Obama left to go to Harvard Law School, where he became the first black president of the law review. He worked as a summer associate at the Sidley Austin law firm in Chicago, where he met his future wife. After graduation from Harvard in 1991, Obama practiced civil rights law at a small firm in Chicago, then became a lecturer in constitutional law at the University of Chicago in 1993.

Elective office: Obama won a seat in the Illinois state Senate in 1996. During his time in the Legislature, he worked on welfare and ethics legislation, as well as a measure requiring electronic recording of police interrogations and confessions in homicide investigations.

Obama won a heavily contested U.S. Senate seat in 2004, carrying 53 percent of the Democratic primary vote in an eight-candidate race. He easily won the general election as well. In the U.S. Senate he compiled a liberal voting record, but was one of the few Democrats to back a measure on class-action lawsuits. He opposed the appointment of Chief Justice John Roberts and Justice Samuel Alito to the U.S. Supreme Court.

The nonpartisan National Journal ranked him as the most liberal member of the U.S. Senate early this year based on his voting record in 2007. He was ranked 10th most liberal in 2006 and 16th most liberal in 2005.

Presidential campaign: Obama announced his presidential candidacy on February 10, 2007. Though New York Sen. Hillary Clinton was initially seen as the front-runner for the Democratic nomination, Obama quickly showed an ability to raise large amounts of money and draw record-breaking crowds who were attracted to his rhetorical skill, his opposition to the Iraq war, and his promise to move beyond the divisive politics of the past 40 years.

Obama won the first contest of the Democratic primary in Iowa in January 2008, but did not clinch the nomination until the last states had cast their ballots in June. During the protracted battle with Clinton, Obama had to explain away a disparaging comment about rural voters and distance himself from a former preacher's incendiary remarks. His campaign developed new ways to mobilize voters through the Internet.

After accepting the Democratic nomination in Denver in August, Obama faced Republican John McCain in the general election. McCain initially led in opinion polls after he picked Alaska Gov. Sarah Palin to be his running mate, but his support eroded amid a souring economy and concern about Palin's qualifications.

Obama won 53 percent of the popular vote on Election Day, November 4.

(Reporting by David Alexander and Andy Sullivan)

(Sources: Reuters, Almanac of American Politics, "The Audacity of Hope" by Barack Obama)