Between 1952 and 2004, the major party Presidential tickets included at least one Southerner between them. In 1992, three of the four candidates hailed from the old Confederacy; from 1980 until 2004, every election but one included at least two Southerners. From 1952 until 1976, one candidate in every election came from the South. Before 2008, the last election not to include a Southerner was 1948, which included candidates from Kentucky and Missouri. Note that this includes George H.W. Bush as a Southerner by virtue of his Texas residency.
Now you know.
UPDATE: Spiro Agnew was, of course, from Maryland; that relieves ’68 of its Southerner.