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US President Barack Obama swept to a emphatic re-election win over Mitt Romney, forging new history by transcending a dragging economy and the stifling unemployment which haunted his first term.
The 44th US president and the first African American to claim the Oval Office, was returned to power after a joyless election which appears to have deepened, rather than healed, his nation's political divides.
"In this election, you, the American people, reminded us that while our road has been hard, while our journey has been long, we have picked ourselves up, we have fought our way back," Obama said at a triumphant victory party in Chicago.
"We know in our hearts that for the United States of America the best is yet to come," Obama said, striving for inspirational heights rarely touched in a campaign where the prophet of hope of 2008 became a conventional, brawling politician.
As Obama's victory was confirmed with wins in rustbelt Ohio and his spiritual political home in Iowa, large crowds suddenly materialised at the White House, chanting "four more years" and "O-bama, O-bama."
Republican nominee Romney, deflated and exhausted, offered Obama a classy tribute, as he appeared before dejected supporters in Boston, moments after phoning the US leader to formally concede and to congratulate his team.
"I wish all of them well but particularly the president, the First Lady and their daughters," Romney said.
"This is a time of great challenges for America and I pray that the president will be successful in guiding our nation."
Obama repaid the compliment in his speech, saying the Romney family "had chosen to give back to America through public service and that is the legacy that we honour and applaud tonight."
And in an intriguing aside, the president said he looked forward to sitting down with his former foe to find if they could find common ground to work together.
Once the euphoria fades, the president will face a tough task enacting his second term agenda, after Republicans, who thwarted him repeatedly in his first term, retained control of the House of Representatives.
Once the euphoria fades, the president will face a tough task enacting his second term agenda, after Republicans, who thwarted him repeatedly in his first term, retained control of the House of Representatives
Democrats kept the Senate but fell short of the 60-vote super majority needed to pass major legislation over Republican blocking tactics.
Obama paved the way to victory with a staunch defence of Democratic bastions in Pennsylvania, Wisconsin and Michigan, at which Romney had taken a last minute run when he saw more conventional paths to victory blocked.
He also locked in swing states, Virginia, which he became the first Democrat to win since 1964 four years ago, Nevada, Ohio, New Hampshire, Colorado and Iowa, crushing Romney's slim hopes of a viable path to victory.
Romney could only wrestle Indiana and North Carolina from Obama's 2008 account.
Obama and Romney were neck-and-neck in Florida, but the final results from the Sunshine State were not expected until Wednesday.
The win in Iowa will be especially sweet for Obama, as the heartland state nurtured his unlikely White House dreams way back in 2007 and a tear rolled down his cheek as he held his last ever campaign rally there late on Monday.
His victory in Ohio represents a delayed repayment for his gutsy call in 2009 to mandate a federal bailout of the auto industry, on which one in eight jobs in the state depend and which Romney opposed.
Obama, no longer a prophet of hope and change, won re-election with a fiercely negative campaign, as he branded Romney, a former multi-millionaire corporate turnaround wizard as indifferent to the woes of the middle class.
Prior to Obama's victory, no president in 70 years had won re-election with the unemployment rate above 7.4 per cent. Although the economy has created more than five million jobs since the Great Recession, the rate is now 7.9 per cent.
Exit polls showed that though only 39 per cent of people believed that the economy was improving, around half of Americans blamed former Republican president George W. Bush for the tenuous situation, and not Obama.
Obama's victory was a complete vindication for a campaign team that had predicted a close, but winnable election, despite the painful after effects of the deepest economic crisis since the 1930s Great Depression.
The president ran for re-election on a platform of offering a "fair shot" to the middle class, of fulfilling his pledge to end the war in Iraq, killing Osama bin Laden, and of building a clean energy economy.
Remarkably, his coalition of Hispanic, African American and young voters, defied expectations and turned out in similar numbers to those of his euphoric change-fuelled campaign in 2008, shocking Romney's team.
Latino voters in particular helped Obama to victory in the desert state of Nevada, and in the Rocky Mountains state of Colorado, US television networks projected.
Republicans had insisted right up to election day that Obama's army, disaffected by busted expectations for his first term, would stay home, and had predicted instead a late Republican wave that would elevate Romney.
Now, Obama will get the chance to protect his historic reforms of health care and Wall Street and may have the chance to shape the Supreme Court for a generation, with several vacancies on the bench expected to arise.
Obama will also likely look abroad as he builds his legacy, but will face an immediate challenge early in 2013 and a possible decision whether to use military force to thwart Iran's nuclear program.
More immediately, at home, Obama will face a swift showdown with Republicans on Capitol Hill, on the so-called "fiscal cliff" involving the expiry of Bush-era tax cuts and a need to raise the US debt ceiling.
Ruinous budget cuts designed to trim the ballooning deficit, which could tip the economy into recession, are also about to come due, unless Obama can reach a deal with Republicans, who have opposed him tooth and nail for four years.
The president may have been helped at the 11th hour when superstorm Sandy roared ashore, killing more than 100 Americans, but giving Obama the chance to publicly pull the levers of government.