user: Question: Who was the winner for the Winton Motor Raceway circuit?
Columns: ['Race Title', 'Circuit', 'City / State', 'Date', 'Winner', 'Team']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Amaroo', 'Amaroo Park', 'Sydney , New South Wales', '21 - 23 Feb', 'Mark Skaife', 'Winfield Team Nissan']
SQL:

assistant: SELECT "Winner" FROM "Table" WHERE "Circuit" = 'Winton Motor Raceway';