user: Question: What was the last year that incumbent Joseph T. Deal was first elected?
Columns: ['District', 'Incumbent', 'Party', 'First elected', 'Result', 'Candidates']
Types: ['text', 'text', 'text', 'real', 'text', 'text']
Sample row: ['Virginia 1', 'S. Otis Bland', 'Democratic', 1918.0, 'Re-elected', 'S. Otis Bland (D) Unopposed']
SQL:

assistant: SELECT "First elected" FROM "Table" WHERE "Incumbent" = 'Joseph T. Deal';