Now that the results are in, the hard work begins. Here are 10 things President Barack Obama can and must do to change the world:
1) Fight climate change
The next presidential term could make or break whether the world takes meaningful action to prevent catastrophic climate change. The US, which consumes more than 20% of the world's energy despite having less than 5% of its population, has continually shirked leadership on climate. But the world has assigned a deadline for collective action: 2015. Obama can support that process and break the oil industry's grip on climate policy by ending fossil fuel subsidies, and help drive through a fair, ambitious and binding climate treaty.
2) Save the two-state solution
Whether it's deserved or not, the Israeli-Palestinian conflict has come to symbolise intractable crisis and global impotence. Talks are at a complete standstill: Israel, through its settlers, continues to colonise the occupied West Bank, and Palestinian leaders remain uselessly divided.
There are a growing number of voices despairing of the possibility of the two-state solution, the two decade old standard peace project that aims to achieve Palestine and Israel living in security side by side. But there may be one last hope to rescue it.
The head of the Palestinian Authority, Mahmoud Abbas, will take his people's bid for statehood back to the UN after the US election. That means that the US, Israel's closest ally and patron, will have one more opportunity to revive the vital two-state solution by supporting Abbas's initiative. So far, the US has blocked it. But Obama could still make it work and from there, the work can begin to build a viable Palestinian state.
3) Get big money out of politics
Private money has always played too big a role in US politics. But in this election cycle things have got completely out of hand. Thanks in large part to the supreme court's 2010 Citizens United decision – allowing corporations, individuals and unions to spend unlimited amounts of cash – as much as $6bn could be spent in this campaign.
It's hard to keep faith in a democratic system when a corporation has the power to swing elections with money. But Obama could avert this disaster for democracy by championing a 28th amendment to overturn Citizens United and limit campaign spending.
4) Real immigration reform
There are an estimated 11.5 million illegal immigrants in the US. Many escaped lives of poverty and hardship in Latin America to come to the US, where they now face predatory job contractors and the risk of deportation. Recent initiatives have made some progress, but much more is needed to balance the country's legal considerations with the basic human dignity of undocumented immigrants. Obama has the opportunity to reform this broken system by opening paths to residency, education and healthcare for millions of hardworking individuals and families – and revising US law to make borders and immigration fair and enforceable.
5) Label genetically modified goods
Monsanto and other big petrochemical companies have had a free pass from the US government. They've peddled genetically modified crops to farmers across the world, they've created super-pesticides, and they've patented seeds to maximise profits at growers' expense.
In the US, GM foods are not labelled and their dangers have not been properly researched. The US department of agriculture has an obligation to rigorously test genetically modified organisms and guarantee that modified seeds and animals will not alter existing ecosystems. Obama has the opportunity to better protect consumers, farmers and the natural world by bringing in more rigorous standards of testing, and stopping the patenting of life forms and the destruction of farming systems. At a very minimum, he can demand the labelling of GM food.
6) Support transition in Syria
What began as a peaceful democratic uprising has descended into a horribly violent civil war. Syrians have braved 18 months of death and hardship: new estimates put the death toll at 31,000, with tens of thousands more "disappeared", and another cold winter approaching. The US and its allies in the Friends of Syria group have repeatedly condemned President Bashar al-Assad's brutal crackdown, but they've yet to foster or genuinely support a viable alternative.
The Obama administration has a real opportunity to help bolster and unite the Syrian opposition, provide assurances to worried minority groups within the country, and elevate nonradical representative groups. If the carnage continues unabated, the president could lead the world in the most effective strategy to ramp up military pressure on Assad to come to the negotiating table.
7) Let the Bush tax cuts for the wealthy expire
This one's a no-brainer. Many rich Americans took a hit in the early days of the financial crisis, but unlike their less wealthy neighbours they have recovered – and then some. So extending President George W Bush's tax cuts for income over $250,000 seems both ridiculous and offensive to tens of millions of hardworking Americans. All Obama and Congress have to do is not extend the Bush tax cuts for the wealthy, and they'll save the government $1 trillion over 10 years. Oh, and in so doing, restore a sense of fairness to US tax policy.
8) Champion marriage equality
Every citizen in the US has the right to live in equality and dignity under the law. But at the moment, despite the success of gay marriage votes in several state polls last night, this simply isn't the reality for gay people in a majority of states in the union. Significant progress has been made in recent years, not least Obama coming out in favour of gay marriage, but as legal battles on this issue spread across the states, strong moral leadership is needed now more than ever.
The role of the president is not to impose his moral views on the nation; it is to lead and inspire. By continuing to call for compassion, acceptance and equality, Obama could help transform American culture – and set an example for the rest of the world.
9) End the drug war
The presidents of Colombia, Guatemala and Mexico have bravely called for a new direction in the war on drugs. The US president could do the right thing and champion a change of this disastrous US-led policy – one that has cost hundreds of thousands of lives, billions of dollars and has failed by every imaginable metric.
Within the US, drug enforcement policy is one of the last pillars of senseless bigotry. Traffickers and addicts alike are locked up, not rehabilitated or treated, streets are militarised, communities are broken. The US has the largest prison population in the world – 25% of those under correctional control are nonviolent drug offenders. And south of the US the war rages: 60,000 people have been killed in Mexico in just six years, and central American countries regularly post some of the world's highest homicide rates.
Real policy change in the US will mean new laws at the state and federal level, and a broad social push in support of decriminalisation (something actually many citizens already support). People, who have been used as an excuse for the "war on drugs", are seeing the cracks and cost of this crazy policy. A change could happen quite fast, if the president admits that the drug war has failed and a new course is needed.
10) Appoint good judges
Here's an area that could be essential to achieving all the rest. Obama will be responsible for appointing dozens of federal judges and at least one supreme court justice. These judges serve for life, and they are the first and final line of deciding whether laws are constitutional. The current administration has failed to appoint judges at pace – in fact, there are more federal vacancies now than four years ago. This is serious. Obama will appoint the judges that hear cases on climate change, campaign finance reform, food safety, gay marriage, drug policy and much more. He must choose well.
What else? You tell us
That's a long list, but each point is achievable. But what have we missed? Leaving Afghanistan; a diplomatic solution to Iran's nuclear programmes; easing tensions with China? Tell us what you think should be on this list, and how the American president should show the leadership to help get there.
Sources: Avaaz, Guardian, National, Politico, Elections not Auctions, New York Times, Los Angeles Times, Economist, Firedoglake, Upworthy, Al Jazeera, Gallup, Real Clear Policy