Oregon Secretary of State Kate Brown (D) will become the first openly bisexual governor in U.S. history when Gov. John Kitzhaber (D) resigns Wednesday.
An open LGBT governor has never been elected, although New Jersey did have an openly gay governor briefly in 2004, after Gov. Jim McGreevey (D) came out as gay and admitted an affair with a man he had appointed to a key job. He resigned three months later. [source]