Here's a political science question that I am unequipped to answer. Are there cases where knowing your opponent far in advance is undesirable? Let me present at least one hypothetical. Let's say you've got a potential opponent that gets chosen early, who has some real skeletons in his closet. This could be good from an oppositional research point of view, in the sense that it gives you time to really nail down your charges, lay out a long-term strategy for leaking the stuff out to the press so as to keep your opponent on his heels, etc. But there's a downside too. If some of the folks on your side get too excited and jump the gun, the oppo research could all come out early and leave you no ammunition for later in the campaign, when people are paying attention. This gives the other side more time to repel the charges, neutralize them, or just plain change the subject. Can our readers think of cases where things worked out this way?