Table: election_results_1920
Columns: district
incumbent
party
first_elected
result
candidates

Question: Who were the candidates when Henry Garland Dupré was incumbent?
SQL: SELECT "candidates" FROM election_results_1920 WHERE "incumbent" = 'Henry Garland Dupré'

Question: How many candidates were there when Henry Garland Dupré was the incumbent? 
SQL: SELECT COUNT("candidates") FROM election_results_1920 WHERE "incumbent" = 'Henry Garland Dupré'

Question: What district did James O'Connor belong to?
SQL: SELECT "district" FROM election_results_1920 WHERE "incumbent" = 'James O''Connor'