He defeated Republican John McCain, a war veteran who spent five years as a prisoner of war and served in the U.S. Senate for 22 years.
Obama bagged 349 electoral votes while his rival McCain secured only 173 in the 538-member electoral college, which formally elects the president and vice president on December 15.
In the electoral college directly elected from 50 states based on their population, a presidential candidate needs 270 votes to secure victory.
As predicted by various opinion polls in the last one month, Obama got 52 percent of popular votes. But McCain was able to do better than predicted.
President-elect Obama, addressing a victory rally in his hometown Chicago, said change has come to America. "Change" had been his campaign slogan for the past 21 months. "If there is anyone out there who doubts that America is a place where anything is possible, who still wonders if the dream of our founders is alive in our time, who still questions the power of our democracy, tonight is your answer."
Thousands of Obama supporters came onto the street rallying the whole night immediately after his victory became certain. More than one million Democrat volunteers were deployed to make sure everyone voted. Volunteers knocked at each and every door and frequently reminded voters to cast their votes.
Because of aggressive campaigning, Obama shattered some of the Republican stronghold states in central and south western America like New Mexico and Colorado, but his victory was guaranteed by the coastal states in the populous north west and the far western states. Pitched battles were fought in Ohio, Florida, Missouri, Pennsylvania, Virginia, Indiana, Georgia and Montana. Obama defeated McCain by a narrow margin of up to 4 percentage points in Florida and Virginia and took a lead of 11 percentage points in Pennsylvania.
According to preliminary analysis, Obama got most of the votes from the country's 11 percent black population and two thirds of the country's 15 percent Hispanic population. Exit polls showed 72 percent of young voters had voted for Obama.
Raised by his maternal grandparents in Hawaii after his parents separated when he was just two-years-old, Obama received advanced degrees from prestigious universities in the U.S. and settled in Chicago, the native place of his wife Michelle.
He started his political career in 1983 as a community organizer in Chicago, served as a state senator in Illinois for seven years and later was elected U.S. senator in 2004.
After 16 months of a protracted race in the party's primary, Obama was officially declared the Democratic Party candidate for the country's chief executive on June 3, defeating Hillary Clinton.
A man with enormous charisma, Obama made his mark in Washington even as a junior senator. His keynote speech at the Democratic National Convention in 2004 was much acclaimed.
In the speech, he said his grandfather worked as a domestic helper and his father used to herd goats in a small Kenyan village. "But my grandfather had larger dreams for his son. Through hard work and perseverance my father got a scholarship to study in a magical place, America, which shone as a beacon of freedom and opportunity to so many who had come before."
He said his parents shared an abiding faith in the possibilities of the U.S. They gave him an African name, Barack, or 'blessed,' believing that in a tolerant America his name would not be a barrier to success. "They imagined me going to the best schools in the land, even though they weren't rich, because in a generous America you don't have to be rich to achieve your potential."
The son of a Kenyan father, who moved from Hawaii to Indonesia into his step-father's home after his mother's remarriage, he later became a member of his maternal grandparents' family in Hawaii. His dreams came true on Tuesday when he became the 44th president of the world's sole super power. His grandma who raised him, however, died Monday, a day before Obama was elected president.
To many, it is all because of "dreams from his father and audacity of hope"- the two issues he chose to write books on after he entered public life - that Obama has become one of the most successful politicians in U.S. history.
To borrow the words of former President Bill Clinton, Obama deserves the presidency for four reasons. "The four things that really matter in a president are: number one, the philosophy; number two, the policies; number three, the ability to make a decision; and number four, the ability to execute that decision and make changes in people's lives," the successful two-term president had said of Obama on Oct. 30.
Obama had a hard time justifying his "association" with some radical professors and his Islamic-sounding middle name - Hussein. Until the last day, Republican rivals attempted to link him with "radicals". In the initial days of the presidential race, he was charged with being educated in an Islamic school in Indonesia where he spent four years from 1967 to 1971 with his stepfather.
Immediately after Obama's victory became certain, his rival McCain and President George W Bush called to congratulate him.
"In a contest as long and difficult as this campaign has been, his success alone commands my respect for his ability and perseverance," said McCain. "But that he managed to do so by inspiring the hopes of so many millions of Americans who had once wrongly believed that they had little at stake or little influence in the election of an American president is something I deeply admire and commend him for achieving."
President Bush told Obama he was about to begin one of the great journeys of his life, and invited him to visit the White House as soon as it could be arranged, according to White House spokeswoman Dana Perino.
source-kantipurnews