Question: Which Incumbent has a District of Massachusetts 2?
SQL: SELECT "Incumbent" FROM "2-1434986-5" WHERE "District" = 'Massachusetts 2';

Question: Which Incumbent has a District of Massachusetts 8?
SQL: SELECT "Incumbent" FROM "2-1434986-5" WHERE "District" = 'Massachusetts 8';

Question: Which District has a First elected larger than 1858?
SQL: SELECT "District" FROM "2-1434986-5" WHERE "First elected" > 1858.0;