CREATE TABLE table_18148 ("District" CLOB, "Incumbent" CLOB, "Party" CLOB, "First elected" FLOAT, "Results" CLOB, "Candidates" CLOB)

When did the elections take place in district Maryland 2?
SELECT MIN("First elected") FROM table_18148 WHERE "District" = 'Maryland 2'
SELECT MIN("First elected") FROM "table_18148" WHERE "District" = 'Maryland 2'