user: Question: Name the total number of districts for first elected being 1998
Columns: ['District', 'Incumbent', 'Party', 'First elected', 'Result', 'Candidates']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Massachusetts 1', 'Richard Neal Redistricted from the 2nd district', 'Democratic', '1988', 'Re-elected', 'Richard Neal (D)']
SQL:

assistant: SELECT COUNT("District") FROM "Table" WHERE "First elected" = '1998';