Another method to consider in pre-spawn is Carolina Rig.  Tie on a Carolina rig and pick a cove that has a nice drop off, saddle, or deeper flat.  Start by working from shallow to deep.  Tie on a watermelon or pumpkinseed Zoom Centipede with 2/0 hook.  Slowly drag this bait back to the boat.  Ensure you are using a rod that has much sensitivity, as you want to be able to feel every rock, twig, or fish biting.  The water will be cold, so move the bait very slow.  Cover every once of train methodically.  If working from shallow to deep doesn’t work, move your boat into the shallow area and cast to deep.  You can catch many fish you are floating over with this technique.