Just minutes into the night shift at Lowe’s, beads of sweat sparkle on Bol Gai Deng’s forehead. He’s at the back of the suburban Richmond store, unloading a 54-foot truck crammed with leaf blowers and barbecue grills, Drano and pitchforks — tough work that drives off most in a matter of weeks or months. Deng has stuck with it for six years because he likes having his days free for his other gig: running for president of South Sudan. Deng’s campaign operates out of Blake’s offices at the Virginia Christian Alliance, which leads battles against abortion and gay rights in the state Capitol. Hundreds of African American Baptists, gathered at a Richmond convention in June, gave Deng a standing ovation, comparing him sympathetically to children fleeing Central America today.