user: Question: Who are all successors when reason for change is Died May 12, 1964?
Columns: ['District', 'Vacator', 'Reason for change', 'Successor', 'Date successor seated']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['California 23rd', 'Clyde Doyle (D)', 'Died March 14, 1963', 'Del M. Clawson (R)', 'June 11, 1963']
SQL:

assistant: SELECT "Successor" FROM "Table" WHERE "Reason for change" = 'Died May 12, 1964';