Because they only poll in cities or do random calling or ask people at only a certain time, i don't know. All I know is that I read the Tribune, it's very biased, and they're not experienced pollsters. It's just like Strategic Vision, Zogby, other unreliable polls. Most people could agree it's Bush +2 in WI, Bush +2 in OH, Kerry +2 in IA, Kerry +2 in MN. That's fair, that seems more accurate, more logical. I don't like polling, even when it does favor the candidate I like. Because there's too many things that could go wrong or are unaccounted for. They also can discourage people from voting if the percentages are greater than 5 or 10% towards one candidate. I like the blue state, red state predictions better.
Do you have any relevant information ( sample not random - for example) beside that you don't like their views.
I know some pollsters who explicitly declare their political views and by no means it discredit their polls.
I know nothing about the Chicago Tribune (Lib, Con etc.) and its immaterial.