user: Question: How many sitting Representatives are there in the New York 10 polling area?
Columns: ['District', 'Incumbent', 'Party', 'First elected', 'Result', 'Candidates']
Types: ['text', 'text', 'text', 'real', 'text', 'text']
Sample row: ['New York 7', 'John J. Delaney', 'Democratic', 1931.0, 'Re-elected', 'John J. Delaney (D) 72.8% Harry Boyarsky (R) 27.2%']
SQL:

assistant: SELECT COUNT("Incumbent") FROM "Table" WHERE "District" = 'New York 10';