Question: What is the date administered where Saxby Chambliss is 54% and Jim Martin is 36%?
SQL: SELECT "Dates administered" FROM "1-16751596-16" WHERE "Republican: Saxby Chambliss" = '54%' AND "Democrat: Jim Martin" = '36%';

Question: How many times did Saxby Chambliss have a lead margin of 21?
SQL: SELECT COUNT("Republican: Saxby Chambliss") FROM "1-16751596-16" WHERE "Lead Margin" = 21.0;