CREATE TABLE table_20683381_2 (date_of_opinion_poll VARCHAR2, undecided VARCHAR2)

How many polls taken on different dates show an undecided percentage of 25%?
SELECT COUNT(date_of_opinion_poll) FROM table_20683381_2 WHERE undecided = "25%"
SELECT COUNT("date_of_opinion_poll") FROM "table_20683381_2" WHERE "25%" = "undecided"