In 2008, Clayton ran unsuccessfully for the Democratic nomination to challenge Tennessee's other U.S. senator, Moderate Republican [[Lamar Alexander]], a former governor of Tennessee and an ex-[[United States Secretary of Education]] whom Clayton then described as a "[[neo-conservative]]".<ref name="mj">{{cite web| url=http://www.motherjones.com/mojo/2012/08/mark-clayton-tennessee-democrats-senate|title=Dems Nominate Anti-Gay Conspiracy Theorist for Senate |work=Mother Jones}}</ref> | In 2008, Clayton ran unsuccessfully for the Democratic nomination to challenge Tennessee's other U.S. senator, Moderate Republican [[Lamar Alexander]], a former governor of Tennessee and an ex-[[United States Secretary of Education]] whom Clayton then described as a "[[neo-conservative]]".<ref name="mj">{{cite web| url=http://www.motherjones.com/mojo/2012/08/mark-clayton-tennessee-democrats-senate|title=Dems Nominate Anti-Gay Conspiracy Theorist for Senate |work=Mother Jones}}</ref> |