user: Question: Who was the incumbent for the election in 1978?
Columns: ['District', 'Incumbent', 'Party', 'Elected', 'Status', 'Result']
Types: ['text', 'text', 'text', 'real', 'text', 'text']
Sample row: ["Georgia's 2nd", 'Sanford Bishop', 'Democratic', 1992.0, 'Re-elected', 'Sanford Bishop (D) 53.97% Darrel Ealum (R) 46.03%']
SQL:

assistant: SELECT "Incumbent" FROM "Table" WHERE "Elected" = 1978.0;