CREATE TABLE table_4001 ("District" CLOB, "Incumbent" CLOB, "Cook" CLOB, "Rothenberg" CLOB, "CQ Politics" CLOB, "Crystal Ball" CLOB)

Who is the incumbent of district pa-8?
SELECT "Incumbent" FROM table_4001 WHERE "District" = 'PA-8'
SELECT "Incumbent" FROM "table_4001" WHERE "District" = 'PA-8'