Table: election_results_1988_4
Columns: district
incumbent
party
first_elected
result
candidates

Question: Which incumbent was first elected in 1958?
SQL: SELECT "incumbent" FROM election_results_1988_4 WHERE "first_elected" = 1958

Question: Who are all the candidates who ran in the district where Ralph Regula is the incumbent?
SQL: SELECT "candidates" FROM election_results_1988_4 WHERE "incumbent" = 'Ralph Regula'

Question: Which party does Del Latta belong to?
SQL: SELECT "party" FROM election_results_1988_4 WHERE "incumbent" = 'Del Latta'

Question: Which party does Tom Luken belong to?
SQL: SELECT "party" FROM election_results_1988_4 WHERE "incumbent" = 'Tom Luken'