Table: op_poll_us_2008
Columns: poll_source
sample_size
margin_of_error
date
democrat
republican

Question: What was the date of the poll with a sample size of 496 where Republican Mike Huckabee was chosen?
SQL: SELECT "date" FROM op_poll_us_2008 WHERE "republican" = 'mike huckabee' AND "sample_size" = 496

Question: What is the sample size of the poll taken on Dec 13-15, 2007 that had a margin of error of more than 4 and resulted with Republican Mike Huckabee?
SQL: SELECT AVG("sample_size") FROM op_poll_us_2008 WHERE "republican" = 'mike huckabee' AND "margin_of_error" > 4 AND "date" = 'dec 13-15, 2007'

Question: Which Democrat was selected in the poll with a sample size smaller than 516 where the Republican chosen was Ron Paul?
SQL: SELECT "democrat" FROM op_poll_us_2008 WHERE "sample_size" < 516 AND "republican" = 'ron paul'