What is Party, when Opinion Research Centre (OPC) is 1.5%?
CREATE TABLE "opinion_poll_summary" (
  "party" text,
  "marplan" text,
  "gallup" text,
  "national_opinion_polls_nop" text,
  "opinion_research_centre_opc" text,
  "harris" text
);
SELECT "party" FROM "opinion_poll_summary" WHERE "opinion_research_centre_opc"='1.5%';