CREATE TABLE table_26643 ("District" TEXT, "Vacator" TEXT, "Reason for change" TEXT, "Successor" TEXT, "Date successor seated" TEXT)

What was the successor for vacant alabama 3rd?
SELECT "Successor" FROM table_26643 WHERE "Vacator" = 'Vacant' AND "District" = 'Alabama 3rd'
SELECT "Successor" FROM "table_26643" WHERE "District" = 'Alabama 3rd' AND "Vacator" = 'Vacant'