CREATE TABLE "table1_1342315_12" (
  "district" text,
  "incumbent" text,
  "party" text,
  "first_elected" real,
  "result" text,
  "candidates" text
);

Question: When was incumbent Leo E. Allen first elected?
SQL: SELECT MIN("first_elected") FROM "table1_1342315_12" WHERE "incumbent"='Leo E. Allen';

Question: Which district has a Republican elected?
SQL: SELECT "district" FROM "table1_1342315_12" WHERE "party"='Republican';