Barack Obama was today facing a harsh new US political reality in the wake of one of the worst Democratic defeats for 70 years.
In midterm election races across America, Republicans pummelled their opponents, capturing the House of Representatives and a fistful of Senate seats.
With some seats still to be counted, the Republicans picked up at least 60 House seats, eclipsing their 54 gains in 1994 and the party's best result since 1938. They also gained at least six Senate seats, falling short of the 10 they needed to gain control of the upper house.
It was a remarkable comeback from two years ago, when many experts expected the party to endure a long time in the political wilderness in the wake of Obama's emphatic 2008 presidential election victory.
Instead, Obama faces a hard political lesson after a hammering that wiped away the last vestiges of the euphoria that swept him to the White House.
The political momentum has swung to the rightwing Tea Party movement, which energised the Republican base and notched up a string of high-profile victories.
The loss of the House is the first major setback Obama has faced in his relatively untroubled political rise from a community worker in Chicago to the presidency, and means that Nancy Pelosi – its first female Speaker – will give way to the Republican John Boehner.
The swap of a liberal San Franciscan woman for a conservative Ohio man is a symbol of the deep shift in US politics heralded by the midterm results.
Boehner said: "It's pretty clear the Obama-Pelosi agenda has been rejected. They want the president to change course. Change course we will," he said.
Pelosi called for party cooperation to avoid gridlock. "We must all strive to find common ground to support the middle class, create jobs, reduce the deficit and move our nation forward," she said.
The Democrats best results came in the Senate races, winning in Colorado, West Virginia and Nevada, where the Senate majority leader, Harry Reid, pulled off a surprise victory against the Tea Party darling Sharron Angle in one of the most bitterly fought contests of the campaign.
California seemed to act as a bulwark holding back the Republican tide.
Not only did Senator Barbara Boxer defeat her Republican challenger, Carly Fiorina, but Jerry Brown beat Meg Whitman to wrest the California governorship back into Democratic hands after eight years of "the Governator", Arnold Schwarzenegger.
However, despite these glimmers of Democratic hope, there was no denying the stark outcome, which included ten new Republican governors.
Republicans will now be able to use their position of power to wage a guerrilla war against Obama in the remaining two years of his presidential term – the next 24 months are likely to be marked by rancorous partisan bickering and little in the way of new legislation.
Indeed, Republicans may even try to undo substantial areas of Obama's legislative achievements, especially his landmark healthcare reforms. During the campaign, many Republican candidates vowed to take measures to stop his healthcare law from being funded.
Obama made a late-night call to Boehner to offer his congratulations and discuss working together to creating jobs and improving the economy.
Although Obama remains favourite to secure re-election in 2012, last night's congressional defeats, as well as the loss of governorships, have removed his air of invincibility.
Tea Party favourite Sarah Palin, and a possible opponent for Obama in 2012, predicted a rough ride ahead for the president.
Writing on Twitter she said the electorate has sent a clear message to Obama. "We'll send our representatives to DC to stop your fundamental transformation of America. Enough is enough," she wrote.
Exit polls yesterday showed that the number one issue for the electorate was the economy, with 86% saying they were concerned about it.
The Tea Party, which did not even exist less than two years ago, has benefited from this anger, and last night established itself as a force in US politics.
Now prominent Tea Party-endorsed politicians have swept into positions of real influence, giving the rebel movement a taste of real power for the first time.
Rand Paul, a Republican candidate backed by the Tea Party, won the Kentucky race for a place in the US Senate. In his victory speech, he said the US was witnessing a "Tea Party tidal wave". He will be joined there by another Tea Party favourite, Marco Rubio, who won in Florida.
But there is no place in the Senate for the most written-about member of the Tea Party, Christine O'Donnell, who put out the now infamous political ad declaring she was not a witch.
O'Donnell, a social conservative, was easily defeated in Delaware, a liberal state where a more mainstream Republican might have had a chance. And the Tea Party candidate for Senate in Alaska, Joe Miller, is also expected to lose out to the Republican Lisa Murkowski, who was standing as a write-in candidate.
Obama is almost certain to be magnanimous at a White House press conference at lunchtime today, and a White House official said it was likely he would call on the Republicans to work with him.
The president is about to set off on a 10-day visit to Asia, but one proposal is that he might invite Republicans to his retreat at Camp David for a summit on how to tackle the economy and other issues.
But both sides are preparing for a series of battles in Congress and in the courts. In a radio interview with a station in Chicago yesterday, Obama said: "My hope is that I can co-operate with Republicans."
But he went on to suggest that such co-operation was unlikely given the agenda the Republicans have already signalled.
"That means that their desire to roll back healthcare reform, that they've already announced, or their desire to roll back financial regulatory reform, that they've already announced – that's going to be their agenda," he said.
