Curtis Gans -- the 'dean' of experts on the American electorate -- was interviewed on C-SPAN on Sept.10. Among the things he mentioned:
1 He's estimating a turnout of between 58 and 60 % (between 118 and 121 million voters). This would be the highest turnout since '68, and would be significantly higher than in recent elections. 2 He said the election could be close, but if it wasn't this would be to Kerry's benefit (i.e. Kerry would win big). 3 Women will probably have a 4% greater share of the vote than men (this is because there are 2 % more women in the population to begin with, and because a greater percentage of women vote than do men). 4 Every poll of voter interest shows 10-15% higher than at this time four years ago. He attributed this to, "the Bush administration has served as a lightening rod. There is a polarized public around the president's policies." 5 "It is almost INCONCEIVABLE that people will not come out. It is an emotional election. It is despite the campaigns, a big picture election." (an exact quote).
There have beem various reports recently of unprecedented numbers of people registereing to vote for the first time, and that the overwhelming majority of these people are being registered by Democratic Party activists.
The 'anecdotal' -- i.e. non-poll -- evidence points to a good possibility of a Kerry landslide.