In the 1948 presidential election, many polls predicted that Thomas Dewey would beat Harry Truman. They were so wrong. The polls were made by telephone, but many Democratic voters had no telephone. So, they were not counted.
Now more people have telephones; and polls, except exit polls, are conducted by telephone. But two things make them inaccurate. Many polls are conducted by robo-dialer and a large number of people hang up when there is silence on the other end. Polls are conducted to numbers that are in some database, but many of those database are based on listed numbers. People with unlisted numbers might not be called. Cell phone numbers generally do not appear in listings. Many young people have cell phones only. So many young people will never be called by polls.
Barack Obama is attracting and energizing many young people. Will a representative number of his supporters be called? Some polls show him getting fewer votes than John McCain. Will John McCain be the 2008 version of 1948's Thomas Dewey?
