Grammy-winning soul singer John Legend was an omnipresent figure during last week’s Democratic National Convention. After performing his new anthem, "Are You Out There," on the convention’s first night, Legend fielded interviews from CNN, MSNBC and a gaggle of reporters from around the country. He was on stage again at Thursday’s rally at Invesco Field, singing the internet hit "Yes We Can" with Will.I.Am before an audience of 70,000. For Legend, who had emerged from humble roots in Springfield, Ohio to become the Obama campaign’s most visible musical surrogate, the moment represented both a political and personal apotheosis.

I caught up with Legend at Harold Ford’s Democratic Leadership Conference party on August 26. It was a private affair for big Democratic donors, party activists and anyone connected enough to get their name on the VIP list. Though the club management had forbidden filming, I slipped into Legend’s dressing room after his performance for an impromptu on-camera chat about his involvement on the Obama campaign, his anti-poverty crusading, and his development into an activist entertainer.

I first met Legend when he was a 16-year-old freshman at the University of Pennsylvania named John Stephens. I lived down the hall from him in Penn’s massive dormitory complex, the quad. At the time, John worked two jobs, commuted regularly to Scranton, Pennsylvania to lead a gospel choir, directed an a capella group on campus, and took five classes. He was usually too busy for the partying and social distractions that characterized student life at Penn. While many other students busied themselves with drinking and carousing, confident that their Ivy League degree would guarantee them a cushy job after school, John was on a mission.

In my spare time, I taught myself to play drums. By senior year, I was performing around Philadelphia in informal bands led by Dave Tozer, a guitarist and aspiring producer from a hardscrabble town in South Jersey. At the same time, I helped run "The Gathering," a hip-hop open mic on campus that drew large crowds from all over. John’s roommate, Devon Harris, DJ’ed the event and helped promote it around town (nearly ten years later, The Gathering, is still an active Philly institution). Devon told his friends he was inspired to make hip-hop by his cousin, Kanye West, a producer from Chicago who had managed to eke out a living making beats. But no one had ever heard of this character or seemed to care who he was. This was 1999, after all.

One night during senior year, I invited John to a jam session at a friend’s home studio in West Philly. To my surprise, he packed up his keyboard and came along. Inside the studio, a converted storefront Baptist church basement with red shag carpet and a trap door that led to a baptismal pool, John met Dave Tozer. After some chit-chat, they launched into a version of "Crusin," the Smokey Robinson ballad. I sat down at the drums and joined in with a pair of brushes. For about an hour, we ran through the classics — Stevie, Marvin, Al Green — until John had to get home.

Soon, John began branching out. He sat in on keys at The Gathering, fronted a few gigs for us, and played a session for Lauryn Hill that gave him his first major album credit.

After graduation, John took a consulting job in New York City. He wasn’t sure if he wanted to pursue music full-time. But he continued performing, singing at clubs around New York with a professional quality band assembled by Dave, who had become his musical director. By this time, Devon’s cousin, Kanye, had developed a national profile and was poised to release his first solo album. Kanye had succeeded by cultivating a unique sound steeped in classic Chicago soul that brought hip-hop away from the plastic glitz of P. Diddy and back to its roots. When Devon introduced Kanye to John’s music, he was blown away. He knew his production style would present the perfect compliment to John’s elegant, gospel-influenced vocals.

John finally quit his job and took up music full-time. Dave, Devon (who now goes by Devo Springsteen), and Kanye produced the bulk of his first album, "Get Lifted." Thanks to John, they each have Grammys on their shelves and platinum record plaques on their walls.

A few months before last year’s Iowa caucus, I asked John if he wanted to participate in Hillary Clinton’s campaign for the presidency. She was up by 20 in the polls and was almost certainly going to be the nominee, I told him. John said he would support her if she won the nomination, but he was backing another candidate in the primary. I arranged a phone call between Hillary and John, but John held fast to his support for Barack Obama. The rest is history.