The historic nature of Barack Obama's bid for the White House inspires many Americans but it also runs the risk of turning off some voters uneasy at the prospect of having history shoved down their throats. Obama will be named this week as the first black nominee of a major US political party and, if he defeats Republican John McCain in November's election, would be the first African American president. At 47, he is also the embodiment for many of the American Dream in which anybody can grow up to be president, including the son of a Kansas mother and an absent Kenyan father with an exotic name who spent his early years living abroad. Many Democrats see his campaign as a step towards bridging the country's racial divide. Black Americans constitute some 12 percent of the population but lag behind in many indexes of social and economic health. Obama's acceptance speech on Thursday falls exactly 45 years after civil rights leader Martin Luther King stood on the steps of the Lincoln Memorial in Washington during the March on Washington and delivered his “I Have a Dream” speech. That 1963 speech has come to embody the ideals of the civil rights movement King led during the turbulent 1960s and is seen as an expression of the country's highest aspirations of equality and justice. But the historical coincidence could also remind some white voters that they are deemed to have been on the wrong side in one of America's most divisive social struggles. There are some people “whose experience in the civil rights movement was a loss of face and the humiliation of being seen as an immoral people and that doesn't go away,” said historian Rick Perlstein. Perlstein said America had sanitized the history of the civil rights movement, taking a movement that provoked deep and violent divisions and making it into something the whole country could rally around. “It has been forgotten that the reason why he (King) is a hero and a great American is because he weathered the status of being the most hated man in America. That's not how we choose to remember it,” he said. Civil rights The civil rights movement effectively began in 1957 when King led a year-long boycott of buses in Montgomery, Alabama, in a bid to end racial segregation on the city's public transport. It achieved some of its main goals with landmark civil rights and voting rights acts in 1964 and 1965, which desegregated public facilities and enabled blacks to vote in the south. King was murdered in 1968 in Memphis, Tennessee. To many Americans black and white, who grew up during segregation and risked their lives for the movement, Obama's rise is a dream almost beyond imaginings. “If someone had told me 45 years ago that this would be happening ... I would have said: ‘Are you crazy, are you out of your mind?' For me this is unreal. This is unbelievable,” said Congressman John Lewis, an African American. As a young activist, Lewis led campaigns against segregation and to register blacks to voters. He was one of a small number of speakers who addressed the March on Washington. Two years later, Alabama police beat him severely during a civil rights march in Selma, Alabama, and fractured his skull. Lewis, considered a moral authority in Congress because of his role in civil rights, said he had been asked to address the rally on Thursday as a link between the two events. Christine King Farris, who is King's older sister and his only living sibling, missed the March on Washington because she was ill. Now 80, she will also miss the nomination speech and plans to watch it on television. “The (US) Constitution promises life, liberty and the pursuit of happiness for all people. We have not always been able to attain that but we are on the way,” she said. “That's what my brother was all about – that we (African Americans) have something to offer.” - Reuters __