Barack Obama has won the US presidential election, and will be the first African-American President in US history.
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Mr Obama said that 'change has come to America' as he gave a victory speech in front of a crowd of 65,000 people.
'The road ahead will be long. Our climb will be steep. We may not get there in one year or even one term, but America, I have never been more hopeful than I am tonight that we will get there,' he said.
He paid tribute to his family and his recently deceased grandmother.
‘I miss them tonight. I know that my debt to them is beyond measure,’ he said.
All the main US media networks have projected that the Democrat Senator from Illinois will defeat his Republican opponent John McCain by an emphatic margin.
Mr Obama, 47, will be inaugurated as the 44th US president on 20 January.
Republican White House candidate John McCain conceded defeat to Mr Obama shortly 4am this morning Irish time, and said he had congratulated his opponent in a phone call.
'The American people have spoken, and they have spoken clearly. A little while ago, I had the honour of calling Senator Barack Obama to congratulate him on being elected the next president of the country that we both love,' he said.
In the national or popular vote Mr Obama currently leads by 52.4% to 46.3%.
He has gained sufficient state victories to earn 349 of the 538 Electoral College votes which actually determine the outcome.
Both North Carolina and Missouri are too close to call with both candidates seeming to have split the vote evenly in both states.
Mr Obama strode to victory by winning the state of Pennsylvania, a key battleground that Mr McCain needed to win to keep his hopes of victory alive.
He also won the mid-western battleground of Ohio and captured New Mexico and Iowa, two states won by George W Bush in 2004, to close out Mr McCain's possible route towards the White House.
Mr Obama also took Florida, giving him a clean sweep of key battleground states.
Thousands of people poured in to Chicago's Grant Park for Mr Obama's election night party.
A total of 65,000 supporters received tickets to attend the party, passing through lengthy security checks to gain access to the event.
Bush congratulates president-elect
President George W Bush congratulated Barack Obama on his election and said Americans could be proud of the history which was made yesterday.
Speaking at the White House, Mr Bush said Senator Obama's win was uplifting for those who witnessed the civil rights struggle.
He promised complete co-operation in the weeks leading up to the moment when the President-elect moves into the White House.
Wave of discontent
Mr Obama rode a wave of voter discontent to a historic White House victory, promising change but constrained by a deep economic crisis and two lingering wars.
Raucous street celebrations erupted across the country, but Mr Obama will have little or no time off to enjoy the victory.
He is expected to start work today on planning a course for his formal takeover on 20 January and putting together a team to tackle the huge challenges at home and abroad.
Initial market reaction was muted. Analysts said Mr Obama's victory had been largely priced in and concerns about the global economy were paramount.
The dollar rose against major currencies following its biggest one-day slide in 13 years, but US stock index futures were down 1.3% to 1.6%.
Mr Obama will face intense pressure to deliver on his campaign promises.
He has vowed to restore US leadership in the world by working closely with foreign allies, to withdraw US troops from Iraq in the first 16 months of his term and to bolster US troop levels in Afghanistan.
But his immediate task will be tackling the US financial crisis, the worst since the Great Depression.
He has proposed another stimulus package that could cost about $175bn and include funding for infrastructure and another round of rebate checks.
Mr Obama took command of the election race in the last month as the financial crisis deepened and as his steady performance in three debates with John McCain appeared to ease lingering doubts among voters.
His judgement on handling the economic crisis appeared to help tip the race in his favour.
Exit polls showed six of every 10 voters listed the economy as the top issue.
On the ground
Carole Coleman, former RTÉ Washington Correspondent, speaking on RTÉ's Today with Pat Kenny, said the election was about the end of the George W Bush era as well as the economy.
Speaking to voters in Maryland, she said she found that many believed this election was about the little guy, poor people and not just about the rich. 'The message to the world is that America can renew itself, can move on,' she was told.
Barack Obama may not be able to meet the expectations being placed in him over the next few years but he has been able to get people working together, she added.
RTÉ presenter Myles Dungan was in Phoenix, Arizona, where the party ended early as it was clear that John McCain would not be taking up residence in the White House.
He reported that despite John McCain being magnanimous in his
speech when mentioning Democrat Barack Obama, the McCain supporters were not and booed when the President-elect's name was mentioned.
Many of the Republicans expressed their hopes for the future of their party as the stragglers chanted 'Sarah, Sarah', in reference to Republican Vice-Presidential candidate Sarah Palin.
Those Mr Duncan spoke to expressed disappointment and concern over the result and continued to cast doubts on the future of the US under an Obama Administration.
Official invitation
Meanwhile, Taoiseach Brian Cowen has sent a message of congratulations to Barack Obama on his election as the 44th President of the United States.
He also extended an official invitation to the President-elect to visit Ireland and his ancestral home in Co Offaly.
He said that 'Barack Obama's remarkable personal story - allied to his eloquence and his huge political talents - sends a powerful message of hope to America's friends across the world.'
He added that he looks forward to 'the President-elect building on America's strong relationships with the EU and other countries around the globe.
For more on the US election click go to RTE.ie/uselection
