Which poll shows Democrat Mary Landrieu with 53% against Republican John Kennedy?
CREATE TABLE "opinion_polling_for_the_united_states_se" (
  "poll_source" text,
  "dates_administered" text,
  "democrat_mary_landrieu" text,
  "republican_john_kennedy" text,
  "lead_margin" real
);
SELECT "republican_john_kennedy" FROM "opinion_polling_for_the_united_states_se" WHERE "democrat_mary_landrieu"='53%';