user: Question: Name the mccain % for Dukes
Columns: ['County', 'McCain %', 'McCain Votes', 'Obama %', 'Obama Votes', 'Others %', 'Others Votes']
Types: ['text', 'text', 'real', 'text', 'real', 'text', 'real']
Sample row: ['Barnstable', '42.1%', 55694.0, '56.1%', 74264.0, '1.8%', 2395.0]
SQL:

assistant: SELECT "McCain %" FROM "Table" WHERE "County" = 'Dukes';