user: Question:  how many first elected with result being Re-elected and incumbent being Gary Ackerman Redistricted from the 7th district
Columns: ['District', 'Incumbent', 'Party', 'First elected', 'Result', 'Candidates']
Types: ['text', 'text', 'text', 'real', 'text', 'text']
Sample row: ['New York2', 'Thomas Downey', 'Democratic', 1974.0, 'Lost reelection Republican gain', 'Rick Lazio (R) 50.8% Thomas Downey (D) 49.2%']
SQL:

assistant: SELECT COUNT("First elected") FROM "Table" WHERE "Result" = 'Re-elected' AND "Incumbent" = 'Gary Ackerman Redistricted from the 7th district';