Johnson’s victory over centrist Paul Vallas is a major achievement for the activist left. : Overcoming a major fundraising gap, accusations that he would “defund” the police and public polling that predicted his defeat, progressive Brandon Johnson, a Cook County commissioner and organizer for the Chicago Teachers Union, won a hotly contested race for mayor of Chicago, the nation’s third-largest city. Johnson, who is a Black leftist and former schoolteacher, defeated former CEO of Chicago Public Schools Paul Vallas, a white technocrat at the conservative edge of the contemporary Democratic coalition.