Pennsylvania, Florida, Ohio, New Hampshire, Virginia; as battleground states became landmark states in a historic victory, it became clear that Barack Obama would be the 44th president of the United States.

As Obama supporters revelled in victory at a rally in his home state of Illinois, joined by their fellows across the nation and across the world, where the story of the first African-American to become president-elect, and at that on a promise of a changed and renewed America, had captured imaginations.

Victory was more than decisive - Obama beating McCain by 338 to 155 electoral votes, CNN reported.

In a concession speech, John McCain urged all Americans to join him in supporting Obama - "whatever our differences, we are all Americans" - in facing the challenges ahead. A visibly emotional McCain called for calm as jeers rose from his supporters at references to Obama.

Incumbent president George Bush, whose term ends when Obama is sworn in as president on January 20 2009, reportedly congratulated his successor soon after networks reported the Obama triumph. The very fact of Bush's unpopularity in office and his grave missteps abroad and at home are seen as contributing to the electorate having opted for change in the form of Obama, and a significant strengthening of Democrats in both houses of congress.

After a prolonged, expensive and bitter battle, the final act went relatively smoothly and quickly. At the outset, McCain had, so networks said, two of his four initial must-win states, South Carolina and Georgia, but initially clarity on Virginia and Indiana was still awaited, until networks said that Obama would take Virginia. CNN then projected West Virginia would go to McCain.

Obama was soon more than a third of the way to the 270 electoral college votes needed to win the presidency. Most major networks accorded Obama victories in a list of states that had been expected to be bagged by the Illinois senator, including New Hampshire, Vermont, Connecticut, Delaware, his home state of Illinois, Maine, Maryland, Massachusetts and New Jersey. To this list was added, not long after initial reports, Minnesota, Wisconsin, New York and Michigan, and after some time, New Mexico. Iowa's seven votes put Obama over the 200 mark.

McCain won Kentucky, South Carolina, Alabama, Oklahoma and Tennessee, but it remained too early to say whether he would pull off further must-win victories in Ohio and Florida. Defeat in Pennsylvania represents a significant setback for McCain if confirmed by further reverses. An announcement some time thereafter that the Republican candidate had won Louisana and Utah was unlikely to have revived hopes in the McCain camp.

As several commentators pointed out, no Republican candidate has won the White House without first getting Ohio. After Pennsylvania, it was a major body blow. In the next few hours, other results and consequent projections made it clear that the blow was fatal.

Obama, however, going by the projected results, did not achieve the landslide on the scale of the "Reagan revolution" results that some had forecast. While Ronald Reagan won the presidency in 1984 with 525 votes to his opponent's 13, bettering his first-term victory of 489 to 49, the Obama-Joe Biden's ticket's defeat of McCain-Sarah Palin is relatively closer to the margins of the Bill Clinton victories of 1992 and 1996.

Networks universally reported long queues, while reporters and callers spoke of queues of lengths extraordinary in US elections for decades. In the competition for ratings, CNN had a rabbit to pull out of the hat, as it made television history by projecting one of its reporters into its New York election centre as a holographic image, live from Chicago, thanks to technology reliant on 35 high-definition cameras used to relay a full-length body image.

Exit polls indicated that nationally, the economy was the key issue for the majority of voters, trailed by Iraq and terrorism at a distant second and third, respectively. The economic woes that reached crisis point some weeks ago have been seen as decisive in winning the election for Obama, to whom Americans are turning for solutions to this crisis, along with solutions to other domestic and foreign policy priorities.