What state had william bigler (d) as a successor)
CREATE TABLE "table1_2417308_3" (
  "state_class" text,
  "vacator" text,
  "reason_for_change" text,
  "successor" text,
  "date_of_successors_formal_installation" text
);
SELECT "state_class" FROM "table1_2417308_3" WHERE "successor"='William Bigler (D)';