We all remember the euphoria, in America and much of the rest of the world, that followed Obama’s election in 2008. Like most of us, I was too young to take part in that campaign and that victory which changed the way people viewed America. Echoing previous leaders such as JFK, Obama’s election seemed to herald a new era for America, and for America’s relations with others. In particular, it united young people from countries across the globe with a sense that things would never be the same again. Since the start of my time at Cambridge last year, I knew I wanted to visit the US to experience the presidential campaigns firsthand and to be involved with Obama’s re-election effort.

I wrote to the campaign in states across the country asking if they would be prepared to have a foreigner campaign with them. Understandably busy, some took months to reply. But the reply from one state, Virginia, was immediate. “We’d be honored to have you”. Virginia is split between a conservative south, and a more moderate and left-leaning north, orientated towards Washington DC. Obama’s 2008 victory in Virginia was the first time a Democratic presidential nominee had won the state since the time of Lyndon Johnson and so, unsurprisingly, Virginia has been one of several closely watched battleground states in this year’s contest. Republican super PACs and the Romney campaign have poured tens of millions of dollars into buying television ads in the state, and Obama and his donors have done much the same.

I arrived in September, thinking that my time with the campaign would mainly consist of knocking on doors and making phone calls, speaking with Democrat-leaning voters to make sure they came out to support Obama on election day. This is the hard graft necessary in almost any political campaign: identifying supporters, persuading the undecided and then making sure those people vote. This kind of voter contact is particularly crucial in a state like Virginia, where the campaign strategy was clear: squeeze every last Democratic vote out of the northern cities in the hope that, as in 2008, the region’s Democrat supporters might outweigh the Republicans in the rest of the state.

While canvassing one Sunday I spoke at length with an elderly Latino woman who said of Obama, “he is such a great man, his family is so beautiful - Michelle, oh! Michelle! I pray for them every night. Why won’t Congress let him act? They won’t let him change things”. She brought me the photos she had of the president and told me how she implores her neighbours to vote for him. The next day, I registered to vote a man who realised that, despite having been convicted of a misdemeanour, he still had the right to cast his ballot in November. Before handing me his registration form he made sure I was from the Obama campaign, saying he wouldn’t trust a Romney volunteer with his information. Most of all I was struck by the people who, even if they only passed me in the street while canvassing, stopped to thank me for what I was doing, without giving a thought to the fact that I was clearly not from Virginia.

Most of my time in Virginia, however, was spent in the campaign office working with the campaign’s voter database and recruiting volunteers. Most rewarding was training others - other interns and local, neighbourhood volunteers - on campaigning, communicating with voters and using the campaign’s systems. ‘Community organising’ is fast becoming an over-used phrase in politics, but giving local people the tools to campaign themselves, rather than always relying on outsiders and professionals from different states, and even different countries, is exactly what the Obama campaign tries to do.

It is not hard to see how a relationship with a neighbour and face-to-face conversations with someone living on the same street are much more effective tools, not only to persuade people to vote, but also to inveigle them to volunteer their time. Despite being a foreigner, without a vote and without a clear stake in the election, I was welcomed into the homes of many supporters and worked with them to help create enthusiastic, autonomous local teams of campaigners, fully versed in the workings of the Obama machine.

When I arrived I saw that a volunteer who had come before me had already added ‘Brits 4 Obama’ to one of the many displays adorning the walls of the campaign office. While one or two voters raised eyebrows when they heard my accent, not a single other office volunteer questioned why I was there or why I felt it so important to contribute.

We all knew why we were there, putting in 11-hour days six or seven days a week. A young lawyer working two jobs, an accountant from Kenya, a veteran campaigner from Chicago, a well-travelled humanitarian worker, a middle-aged Australian, students and graduates from America, the Netherlands and others from Britain; the team was anything but unvaried and one of the best aspects of my time with the campaign was working alongside such different people.

Having to leave the campaign as it is reaching its peak has been painful. But I know the team I was once part of will go on trying to make a difference, trying to give ordinary people the power to organise in their communities and to inspire and excite their neighbours.

I know that the Latino woman I spoke to on that doorstep in Virginia will still be there, day after day, making the case for Obama with her family and friends. For her, Obama is not the disappointment some tell us he is; for her, he still represents hope.