user: Question: What candidates ran in the election that included John Shelley?
Columns: ['District', 'Incumbent', 'Party', 'First elected', 'Result', 'Candidates']
Types: ['text', 'text', 'text', 'real', 'text', 'text']
Sample row: ['California 2', 'Clair Engle', 'Democratic', 1943.0, 'Re-elected', '√ Clair Engle (D) Unopposed']
SQL:

assistant: SELECT "Candidates" FROM "Table" WHERE "Incumbent" = 'John Shelley';