CREATE TABLE table_26637 ("State  ( class ) " CLOB, "Vacator" CLOB, "Reason for change" CLOB, "Successor" CLOB, "Date of successors formal installation" CLOB)

What state had william bigler (d) as a successor)
SELECT "State (class)" FROM table_26637 WHERE "Successor" = 'William Bigler (D)'
SELECT "State (class)" FROM "table_26637" WHERE "Successor" = 'William Bigler (D)'