Are the Polls be Accurate?

According to Mark Blumenthal at National Journal, there are three factors at work that may cause polls to be way off this year. They are:

1. 20% of all households don't have a landline and they are mostly younger voters

2. The "Bradley Effect" in which white voters tell pollsters they will vote for a black guy but don't

3. Likely voter models may not capture the electorate correctly


"Will the 2008 election be polling's 'perfect storm'? Pollsters rarely say it in so many words, but when they compare notes these days, worry is the prevailing theme. Three big challenges loom that threaten to throw off survey estimates for the matchup between John McCain and Barack Obama." National Journal Online - Will Winds Of Change Blow Pollsters Away?