CREATE TABLE table_2629 ("District" CLOB, "Vacator" CLOB, "Reason for change" CLOB, "Successor" CLOB, "Date successor seated" CLOB)

Name the date successor seated for failure to elect
SELECT "Date successor seated" FROM table_2629 WHERE "Reason for change" = 'failure to elect'
SELECT "Date successor seated" FROM "table_2629" WHERE "Reason for change" = 'failure to elect'