(dpa) - He's billed as a black John F Kennedy who soars above America's racial divide. He speaks powerfully of leaving the past behind and uniting Americans hungry for change. It all paid off for Barack Obama on Super Tuesday.
This year's youngest candidate at age 46, Obama scored a crucial success, winning states across the nation on the biggest voting day of the Democratic race to pick a presidential candidate for November.
Obama's youth and stirring rhetoric help explain his appeal and prompt some to compare him with Kennedy, who became president at 43 after eight years of Republican rule. Obama was endorsed by the slain president's publicity-shy daughter, Caroline, and brother Edward Kennedy, an icon of the US left.
While rival Hillary Clinton is steeped in the "counterculture" battles of the late 1960s, Obama's engagement is rooted in the more sober 1980s, at least two decades removed from the civil-rights era that shaped an earlier generation of African-American leaders.
Obama "has created in the party's rank and file a feeling of liberation - from intimidation by Republicans, from old divisions, from history itself," Washington Post columnist EJ Dionne said.
While he would be the first African-American president and his speech cadences sometimes carry distant echoes of the late civil rights leader Martin Luther King Jr, Obama presents himself as post- racial.
The image resonates in a nation where blacks have made huge progress since the 1960s but still face disadvantages. It also reflects Obama's own heritage as the son of a Kenyan father and a white single mother from Kansas, a background that sent him on a search for his black roots - and how to transcend them.
He lived with his mother's parents in Hawaii and spent part of his childhood in Indonesia when his mother followed her second husband to his native land. As he grew into adulthood, Obama's quest to find his place in US society - and come to terms with the African father he hardly knew - helped shape his personality and ambition.
Out of college in the early 1980s, he organised poor African- Americans in Chicago to bring neighbourhood grievances to local officials. He went on to Harvard, becoming the first black editor of the prestigious Harvard Law Review, then returned to Chicago to organise voters in 1992.
In 1996, he was elected to the Illinois state senate. He surged to national attention four years ago with a powerful speech at the Democratic presidential convention and won a US Senate seat in 2004.
While Clinton was already in the Senate and voted to authorise the 2003 US-led invasion of Iraq, Obama stresses his consistent opposition to the war. He says he wants to have US troops out by 2009.
Sceptics, including Clinton's camp, question whether he is ready to run for president. Obama insists he is - and that he can beat a Republican in November.
"It is a choice not between black and white, not between genders and regions or religions, but a choice between the past and the future," he told a rally this week.