His book, A People's War on Poverty: Urban Politics and Grassroots Activists in Houston, was published by the University of Georgia Press in 2014 and has received overwhelmingly positive scholarly reviews. Portions of his research have also been published in anthologies by the University of Georgia Press and the University of North Texas Press. Phelps has also been the recipient of the Albert J. Beveridge Grant from the American Historical Association and the Moody Research Grant from the Lyndon Baines Johnson Foundation. Phelps's current research continues to focus on grassroots democracy in the urban South by looking at the politics of race and sexuality in the recent past.