CREATE TABLE table_43585 ("Poll Source" CLOB, "Dates administered" CLOB, "Democrat: Mary Landrieu" CLOB, "Republican: John Kennedy" CLOB, "Lead Margin" FLOAT)

What was the date of the poll from Survey USA that showed a lead margin smaller than 5.5?
SELECT "Dates administered" FROM table_43585 WHERE "Lead Margin" < '5.5' AND "Poll Source" = 'survey usa'
SELECT "Dates administered" FROM "table_43585" WHERE "Lead Margin" < '5.5' AND "Poll Source" = 'survey usa'