Barack Obama's victory comes just a week after Super Storm Sandy swamped large parts of New York, a city which has been a Democrat stronghold for nearly three decades.
As New Yorkers wake up to four more years of Barack Obama, ITV News reporter Lucy Watson gauged reaction in the beleaguered city to the President's second term.
As Nick Clegg took the place of David Cameron at Prime Minister's Questions he sent his congratulations to President Obama.
His sentiments were greeted with cheers from both sides of the House, leading the Deputy Prime Minister to quip that those would be the only cheers he received from the Labour benches:
– Nick Clegg, Deputy Prime Minister
I'm sure the House will wish to join me in congratulating President Obama on election victory last night.
I suspect that's the only point I'll be cheered today by the benches opposite.
But we look forward to continuing the Government's work with him in building a more prosperous, a more free and a more stable world.
The Prime Minister of Lebanon has hailed the 'respect and civility' shown in the US election debates between Mitt Romney and Barack Obama as he congratulated Obama on his win:
Congratulations to re-elected US President Barack Obama! Respect &civility in US elections debates was impressive.
International singers have tweeted their support for Barack Obama.
Canadian Justin Bieber, Georgia-born Katie Melua and Brit Harry Styles have all been showing their support for the President:
alot of emotions right now. congrats President Obama...Im Canadian. Im good. #FreeHealthcare :)
Congratulations Mr Obama
I'm not even American, but I'm glad Obama won.
Staunch Republican Donald Trump has taken to Twitter to launch an attack on the election results, calling it "a travesty" and an "injustice".
We can't let this happen. We should march on Washington and stop this travesty. Our nation is totally divided!
Lets fight like hell and stop this great and disgusting injustice! The world is laughing at us.
Our country is now in serious and unprecedented trouble...like never before.
David Cameron, who is currently on a tour of the Middle East, has praised Barack Obama on his re-election and called him a "very successful US president".
Congratulations to @barackobama - great victory based on building fairer economy and optimism about what politics can achieve
Obama supporters have been celebrating across the USA, in Washington outside of the White House supporters chanted 'four more years' and one jubilant supporter said, "I'm so excited, it's incredible!"
As Barack Obama celebrates his re-election, talk on social networks in America has already turned to the 2016 presidential election, with #Hillary2016 trending on Twitter in the USA.
Support for Secretary of State Hillary Clinton has remained high since she battled Obama for the Democratic nomination in 2008.
I know I'm thinking way to far in the future, but I really wouldn't mind Hillary Clinton being the 45th president. #hillary2016
Israel Defence Minister Ehud Barak congratulated US President Barack Obama on his election victory. The Minister also congratulated all of the Senators and Members of the House of Representatives.
– Israeli Defence Minister, Ehud Barak
I have no doubt that the Obama administration will continue its policy – whereby Israel’s security is at its very foundations – as well as its efforts to tackle the challenges facing all of us in the region; all the while continuing to strive for further progress in the peace process.
I believe that in the tradition of deep friendship and with a backdrop of shared experiences accrued with President Obama, it also will be possible to overcome any differences in stance; should they arise.
Minister Barak wished President Obama, "great success with the tasks that are yet before him."