Civil rights protests and election outcomes : exploring the effects of the poor people's campaign / D. Mark Anderson (Montana State University, IZA and NBER), Kerwin Kofi Charles (Yale University and NBER), Krzysztof Karbownik (Emory University, IZA and NBER), Daniel I. Rees (Universidad Carlos III de Madrid and IZA), Camila Steffens (Universidad Carlos III de Madrid) ; IZA Institute of Labor Economics