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

Question: How many district has a candidate that was first elected on 1811?
SQL: SELECT COUNT("district") FROM "united_states_house_of_representatives_e" WHERE "first_elected"='1811';