http://en.wikipedia.org/wiki/Dewey_Defeats_Truman For many technical reasons all them vaunted polls are wrong... and I suspect we are in for a pleasant surprise.
Realize I know why HISTORICALLY I should be wrong... but I suspect the special brand of Crazee the GOP is unleashing... more folks will vote than usual, and exactly the type of voter that them polls ain't reaching.
As to worried, people are... and people will vote, people are talking to neighbors and the rest. But the media is doing 'xactly what a right wing controlled (and all but free) media has been doing since at least 2000.