In the United States in 1923 and 1924, candidates from both parties who were explicitly endorsed by the Ku Klux Klan ran for governor in Texas, Arkansas, Maine, Arizona and Michigan. Candidates for governor in Kansas and mayor in Minneapolis and Houston were also rumoured to have the Klan's backing, though, at least in some cases, the men denied the claim. A candidate for city commissioner in Houston won election with the Klan's backing; three opposed by the Klan won, too.
In New Jersey, Frank Appleby won the endorsement of the Klan for his 1924 race for the US House after his opponent was "visited by a Klan delegation which demanded that he discharge his secretary, McGrath, on the grounds that he was a Catholic", according to a New York Times account from 1924. Major Stanley Washburn stuck by McGrath. Appleby won - but died before he could take office.
In Kansas that same year, William Allen White, the Progressive editor of the Emporia Gazette, decided to challenge the Republican nominee for governor, Ben Paulen, on the grounds that Paulen "had received Klan support in the primary, had prevented the Republicans from adopting an anti-Klan resolution and 'by silence has further tied the Klan to him and disgraced his party in Kansas'," in White's estimation. White lost, too.
Charles Bowles ran for mayor of the city of Detroit in 1924, with the Klan promising "a national fete" should he win. In that election, the New York Times reported in 1930, the Klan tried to ally with black and Jewish voters to oppose the Roman Catholics. Bowles lost, won in 1930 - and was recalled eight months into his tenure.
On Monday, after Donald Trump declined to reject support from white supremacists in an interview with CNN, it was noted that his father Fred Trump was arrested in 1927 after a Klan march in Queens became violent.