CREATE TABLE table_18685 ("District" CLOB, "Incumbent" CLOB, "Party" CLOB, "First elected" FLOAT, "Result" CLOB, "Candidates" CLOB)

Name the number of incumbents for texas 12
SELECT COUNT("Incumbent") FROM table_18685 WHERE "District" = 'Texas 12'
SELECT COUNT("Incumbent") FROM "table_18685" WHERE "District" = 'Texas 12'