CREATE TABLE table_16751596_12 (republican VARCHAR, dates_administered VARCHAR)

On June 30, 2008 who what was the Republican: Jeff Sessions percentage?
SELECT republican AS :_jeff_sessions FROM table_16751596_12 WHERE dates_administered = "June 30, 2008"
SELECT "republican" AS :_jeff_sessions FROM "table_16751596_12" WHERE "June 30, 2008" = "dates_administered"