I have a column in the Wall Street Journal today on how to read the polls. I have been influenced, as careful readers might guess, by looking ahead to my work with the Decision Desk at Fox News Channel on election night. Exit polls in recent presidential contests have tended to show Democrats doing better than they actually did, and exit polls in most of the Democratic primaries this year showed Barack Obama doing better than he actually did. So, we can be pretty sure that when the first Edison/Mitofsky exit poll numbers are released to media clients, including Fox News, around 5 p.m., they will show Obama ahead. But will that forecast the result? My view is that we should be very cautious in our use of those numbers.