As a project coordinator for NYPIRG on the City College of New York campus in Harlem for three months in 1985, Obama spent hours with students in the trailer that served as the group’s office just below 140th Street and Convent Avenue, giving lessons on how to organize rallies and letter-writing campaigns, how to speak to legislators and lobby for change in public policy.

Former colleagues recall a “fabulously intelligent” and confident young man who was intensely interested in the idea of creating political change from the ground up, an idea that would resurface years later in his meteoric political rise.

He stood apart from some of the more radical students on campus, they said, and believed strongly in working within the system.

“He had a seriousness of purpose,” recalled Diana Mitsu Klos, then a school organizer working out of the CCNY office. “His tenure was brief but anyone who met him received a strong and lasting impression.”

Obama worked that spring semester, from February through late May, on several NYPIRG projects, including the Straphangers Campaign.

Alison Kelley, who was a sophomore at CCNY and later became board chairman for NYPIRG, remembers working with Obama to improve the City College subway station at 137th Street and Broadway, which was dirty and had poor lighting. Kelley said she remembers Obama's tenure at NYPIRG as being in the spring semester of 1984.

On May 1, Obama and others traveled to different stations as part of a “May Day” push to bring attention to the system’s problems and get people to sign letters addressed to local officials and the MTA.

She said he was among the early leaders in the successful push to get CUNY to divest itself of holdings in apartheid South Africa. He also led voter registration drives and campaigns to keep tuition down at CUNY.

“We had other organizers who were competent people but he really stood out,” said Kelley. “Everyone knew that he was going to do something remarkable.”

While admiration and respect for Obama was no doubt inspired by the work he did, Kelley said for some of those around him, it went a little further.

“I had a crush on him," she said. "Every single female had a crush on him.”

Still, Kelley and others said they sensed a restlessness in the future president, a desire to begin a new chapter. Obama has written little about his life in New York; he has described his years at Columbia as a time of isolation and was once quoted as saying he lived “like a monk.”

Shortly after working for NYPIRG, Obama moved to Chicago.

When he told Hershenov he was leaving, she literally got down on her knees and begged him to stay, she said.

“I wanted him to stay because he could appeal to so many different people,” Hershenov said. “People who were very interested in identity politics, people who were apolitical and people on the left and the right. He appealed to students across a political spectrum.”