CREATE TABLE table_12028 ("Race" TEXT, "Length" TEXT, "Class" TEXT, "Circuit" TEXT, "Date" TEXT)

On which date was the Dodge Dealers Grand Prix GTS class race?
SELECT "Date" FROM table_12028 WHERE "Race" = 'dodge dealers grand prix' AND "Class" = 'gts'
SELECT "Date" FROM "table_12028" WHERE "Class" = 'gts' AND "Race" = 'dodge dealers grand prix'