user: Question: From which party is the incumbent who was first elected to office in 1990?
Columns: ['District', 'Incumbent', 'Party', 'First elected', 'Results']
Types: ['text', 'text', 'text', 'real', 'text']
Sample row: ['Iowa 1', 'Jim Nussle', 'Republican', 1990.0, 'Retired to run for Governor Democratic gain']
SQL:

assistant: SELECT "Party" FROM "Table" WHERE "First elected" = 1990.0;