user: Question: Who had most laps led at Chicagoland Speedway? 
Columns: ['Rnd', 'Date', 'Race Name', 'Track', 'Location', 'Pole position', 'Fastest lap', 'Most Laps Led', 'Winner']
Types: ['real', 'text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'March 6', 'Toyota Indy 300', 'Homestead-Miami Speedway', 'Homestead, Florida', 'Tomas Scheckter', 'Buddy Rice', 'Dan Wheldon', 'Dan Wheldon']
SQL:

assistant: SELECT "Most Laps Led" FROM "Table" WHERE "Track" = 'Chicagoland Speedway';