EVANSVILLE, Ind.—Barack Obama's rapid rise from relative obscurity toward winning the Democratic Party nomination for U.S. president hit another bump when he lost to rival Hillary Clinton in Pennsylvania.
Obama's defeat Tuesday in the state's nominating contest slowed his momentum, but he still holds the lead in delegates who will decide the party's nominee to run against Republican John McCain in the November presidential election.
Just four years after he burst onto the national political scene with a keynote speech at the Democratic Party convention, the questions for those deciding whether to support Obama have been mostly about his relative inexperience.
Is the 46-year-old first-term senator who would be the first black U.S. president just a "phenomenon" desired by a war-weary nation eager for a fresh face or does he have what it takes to be an effective president?
Obama cast his scant time on the national political scene as an advantage, saying it meant his hope and ideals had not been compromised. His rousing oratory and can-do message struck a chord early with the public, drawing large crowds and enthusing young voters.
Doubts over whether voters were 'ready' for a black president diminished as he steadily chipped away at Clinton's large early lead and eventually moved past her in the long run-up to the presidential election.
Once the race was down to two Democratic candidates, there was little to distinguish them on policy issues.
Obama often points to his roots—his father was Kenyan and his mother a white woman from Kansas—as one reason he should be picked to run the country, saying he is representative of multicultural America.
One of his favorite lines—"When you're a black guy named Barack Obama and you're running for president you've got to have hope"—regularly draws laughs.
But it is clear Obama has also asked serious questions about his heritage.
A two-time bestselling author who also won two Grammy awards for the audio version of his books, Obama chronicled his struggles to understand himself and his race in 1995 in Dreams from My Father: A Story of Race and Inheritance.
He followed up the memoir in 2006 with The Audacity of Hope: Thoughts on Reclaiming the American Dream outlining his political principles.
While attracting wide support among African Americans, Obama eschewed the rhetoric of race struggle and structured his campaign to appeal to all races.
He has also described himself as a "blank screen" on which people of all different political leanings can project their own views.
As he moved ahead in the polls and the race for delegates who pick the party nominee, Democratic and Republican opponents took a closer look at his record and associates.
Video of Jeremiah Wright, his black pastor at the Trinity United Church of Christ in Chicago, giving racially and politically charged sermons, including saying U.S. policies were partially responsible for Sept. 11 attacks, surfaced on the Internet in March.
Obama, who borrowed the words "audacity of hope" from Wright, was forced to disavow his pastor and ended up giving a much-praised speech on race in America.
Suddenly, every word and action was under a microscope. Comments to a closed-door fund-raiser earlier this month saying small town voters would "cling" to their guns and religion because they were "bitter" over their economic conditions caused a storm of criticism.
Obama, who is married with two daughters, was brought up in Hawaii and Indonesia, raised by his mother and her parents.
His father, from a small village in Kenya, met his mother while on a scholarship to study in Hawaii but left two years after Obama was born.
After graduating from college in 1983, Obama worked as a community organizer for a church-based group seeking to improve living conditions in poor Chicago neighborhoods before entering Harvard Law School where he was chosen as the first black president of the Harvard Law Review.
He jumped into politics in 1996 and served in the Illinois State Senate for eight years. After a failed run for U.S. Congress in 2000, Obama tried his hand at national politics again in 2004 and ran for the U.S. Senate seat from Illinois.
Luck played a role when Obama won a landslide victory against a stand-in Republican candidate after scandals felled first his top Democratic, then Republican, rivals.
After an star turn as keynote speaker at the 2004 Democratic Party convention in Boston, Obama was thrust into the role of presidential contender in a then wide-open race.
His Pennsylvania loss on Tuesday was the latest chapter in what became a drawn-out battle with Clinton after other contenders dropped out following the early state results.