Mark Dudley Obenshain is an American attorney and politician. He is currently serving as a member of the Senate of Virginia from Harrisonburg. He is a member of the Republican Party. He took office in 2004. At the 2013 state Republican convention he became the Republican nominee in the 2013 election for Attorney General of Virginia.

The Senate of Virginia is the upper house of the Virginia General Assembly. The Senate is composed of 40 senators representing an equal number of single-member constituent districts. The Senate is presided over by the lieutenant governor of Virginia. Prior to the American War of Independence, the upper house of the General Assembly was represented by the Virginia Governor's Council, consisting of up to 12 executive counselors appointed by the colonial royal governor as advisers and jurists.