Table: house_1824_elections
Columns: district
incumbent
party
first_elected
result
candidates

Question: What party did robert p. letcher represent?
SQL: SELECT "party" FROM house_1824_elections WHERE "incumbent" = 'Robert P. Letcher'

Question: What district(s) did henry clay represent?
SQL: SELECT "district" FROM house_1824_elections WHERE "incumbent" = 'Henry Clay'

Question: Who were the candidates for election that had a result of a retired jacksonian gain?
SQL: SELECT "candidates" FROM house_1824_elections WHERE "result" = 'Retired Jacksonian gain'