On a biographical level, Demings is a great fit for the Biden campaign. As the child of a maid and a janitor and as a first-generation college student, she’d bolster Biden’s appeal as a working-class Democrat. Her background as a police chief might also resonate with some of the blue-collar former Democrats who have drifted toward the GOP in recent years. As an African American woman, she’d balance out the ticket demographically and would personally represent the party’s most loyal bloc of voters. And it doesn’t hurt that she’s from Florida, one of the key swing states.
She’d also reinforce his strengths on politics and policy.
Biden wants to argue that Trump is an aberration — that he’s uniquely corrupt, incompetent and unempathetic. Demings has more practice advancing the “corrupt” part of that argument than almost anyone: She was one of the managers of Trump’s impeachment in the House.
She’d also mesh well with Biden on major policy issues.