CREATE TABLE table_11501 ("party" CLOB, "Manhattan" CLOB, "The Bronx" CLOB, "Brooklyn" CLOB, "Queens" CLOB, "Richmond [Staten Is.]" CLOB, "Total" FLOAT)

How many voters were in Manhattan when 181,639 people voted in the Bronx?
SELECT "Richmond [Staten Is.]" FROM table_11501 WHERE "The Bronx" = '181,639'
SELECT "Richmond [Staten Is.]" FROM "table_11501" WHERE "The Bronx" = '181,639'