The worst-case scenarios for the Democrats in the midterm elections are bad indeed, Nate Silver warns. He cites "one reasonably well-informed translation of the generic ballot polls" that forecasts a 51-seat loss in the House if the elections were held today. It's not too late to shift the momentum, but he says people are "underestimating the magnitude of losses that might occur if momentum fails to change, or moves in the other direction."
Scenarios that involve dozens of lost seats may not eventually play out, but they are "frankly on the table," he writes for FiveThirtyEight.com. "If Democrats were to lose 50, 60, 70 or even more House seats, it would not totally shock me. Nor would it shock me if they merely lost 15, or 20. But their downside case could be very far down. " (More midterm elections stories.)