The Rev. Benhase's election came Saturday on the second ballot of the electing convention held in Dublin.
The Rev. Benhase is rector of St. Alban's Episcopal Church in Washington, D.C. He has also served parishes in North Carolina, Virginia, Ohio and Indiana.
He replaces the Rt. Rev. Henry Louttit, who is retiring.
The diocese includes Albany, Augusta and Savannah and all towns south.