Table: election_results_2006
Columns: district
incumbent
party
first_elected
results
candidates

Question: What is the district when the first elected was in 1986?
SQL: SELECT "district" FROM election_results_2006 WHERE "first_elected" = 1986

Question: Who were the candidates when the first elected was a republican in 1998? 
SQL: SELECT "candidates" FROM election_results_2006 WHERE "first_elected" = 1998 AND "party" = 'Republican'