When Barack Obama burst onto the national political scene, Laura Hubka, like so many other young Democrats, became politically active for the first time in her life. “I was like ‘Wow! Change and hope, so exciting,’” she recalled in an interview last June. Obama’s lofty rhetoric inspired Hubka to join the Democratic Party in her home state of Iowa, rising to become party chairwoman of Howard County, in the rural northeast part of the state. A decade later, Obama is out of office, Democrats are out of power, and Hubka says the hope she once felt has changed into despair...