Power of the Posse

By Julie Blair

New York

Rico Blancaflor can clearly remember the demographics of his dormitory at Vanderbilt University during his freshman year. Every resident on his floor was white, male, and a member of a Southern fraternity.

The Nashville, Tenn., campus felt like a "war zone," he says, for students of color. The son of Filipino immigrants, Blancaflor chose not to unpack his bags. Every day for several weeks, he contemplated returning to New York City, his hometown.

But he didn't go home. Instead, he looked for support from his "posse," a team of seven friends from New York recruited by the Posse Foundation to promote diversity on...