user: Question: Who was the successor for the New seat?
Columns: ['State (class)', 'Vacator', 'Reason for change', 'Successor', 'Date of successors formal installation']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Maryland (3)', 'Vacant', 'Sen. Thomas H. Hicks died during previous congress', 'John Creswell (UU)', 'March 9, 1865']
SQL:

assistant: SELECT "Successor" FROM "Table" WHERE "Vacator" = 'New seat';