Table: election_results_2006_9
Columns: district
incumbent
party
first_elected
results

Question: What district re-elected a Republican?
SQL: SELECT "district" FROM election_results_2006_9 WHERE "party" = 'republican' AND "results" = 're-elected'

Question: Which incumbent was first elected in 1987?
SQL: SELECT "incumbent" FROM election_results_2006_9 WHERE "first_elected" = 1987