CREATE TABLE "colorado" (
  "district" text,
  "incumbent" text,
  "party" text,
  "first_elected" real,
  "results" text
);

Question: Who is the incumbent for the Colorado 4 district?
SQL: SELECT "incumbent" FROM "colorado" WHERE "district"='colorado 4';

Question: What district is the incumbent Republican and the incumbent retired to run for governor democratic gain?
SQL: SELECT "district" FROM "colorado" WHERE "party"='republican' AND "results"='retired to run for governor democratic gain';

Question: In Colorado 6 district what is the party?
SQL: SELECT "party" FROM "colorado" WHERE "district"='colorado 6';