Hindsight is 20/20, but sometimes foresight is pretty clear, too. The Hill 2010 Midterm Election Poll, conducted over the past four weeks in 42 toss-up House districts, paints a clear picture of danger for Democrats.In those races, all but two of which are currently in Democratic hands, Republican challengers were found to be ahead in 31. The Dems still held the edge in seven, and four were tied. That 31, added to some 15 Dem seats that are so lost they weren’t even worth polling, would put the GOP pickup at 46 if voter sentiment does not change. But...