“Something that scares me, quite honestly more than this administration, is the inept, bloated, corrupt Republican Party led by the McCains, Romneys and — God forgive us — John Boehners of the world, who really have enabled this administration,” said Frank Bellistri, 66, who attended a town hall with Fiorina in Sandown, N.H., over Labor Day weekend. “As much as they go on their own they have enabled them, and it has really run roughshod on everyone in this room.”

The room burst into applause, and Fiorina was glad to chime in. “I worked hard to help elect a historic Republican majority in the House and to restore a Republican majority in the Senate,” she said. “And not a lot has changed. It is a leader’s job to produce results. And so I agree that the results have been thin and the results need to be coming, or we need different leadership.”

The parties have wandered into similar territory in other years, but they have never earned this sort of backlash. In 1999, a Republican Party that controlled Congress failed to achieve a conservative goal — removing Bill Clinton from office. Its base got behind George W. Bush, a Texas governor who talked about “compassionate conservatism” and compromise with Democrats. In 2007, a resurgent Democratic Party failed to cut funds for the war in Iraq, the issue that had won the midterms. Its primary voters split almost evenly between then-senators Hillary Rodham Clinton and Barack Obama, who had been there when the war was not just funded, but expanded.