CREATE TABLE table_16751596_13 (democrat VARCHAR, dates_administered VARCHAR)

What was Mark Begich polling on October 6, 2008?
SELECT democrat AS :_mark_begich FROM table_16751596_13 WHERE dates_administered = "October 6, 2008"
SELECT "democrat" AS :_mark_begich FROM "table_16751596_13" WHERE "October 6, 2008" = "dates_administered"