In the current shutdown, John Boehner might be acting out of fear of losing his position. If he doesn’t appease the hardliners who are willing to take the government and economy over the brink for their goals, he could be ejected from the Speaker’s seat. However, is there some chance that he’ll lose his position another way – by Republicans losing the House majority in January 2015?

Usually, the President’s party loses House seats at the midterm election. The normal expectation would be for Republicans to gain seats in 2014. But exceptions can happen, for instance in 1998, when Democrats picked up five seats. That came after a rough few years during which Speaker Newt Gingrich led the way to the last substantial shutdown.

On the other side of the coin, House Republicans enjoy an exceptional advantage in the form of gerrymandered districts. In the 2012 elections, Democrats won the national popular vote by 1.5%, but they needed a 7.3% margin to take control. So broadly speaking, opinion would have to swing by about 6% or more for control of the House to become competitive.

Where is public sentiment today? Before the shutdown, three generic Congressional preference polls taken Sept. 23-29 (Quinnipiac, Rasmussen, PPP) show an average of Democrats +6.0+/-1.5%. That’s a swing of less than 5%…before the shutdown.

A provocative set of district-level polls was conducted for MoveOn by PPP. These are partisan organizations, but I note that of major pollsters, PPP had the best accuracy in 2012. Also, even the worst house biases are no more than three percent. So keep that in mind.

PPP surveyed 24 Congressional districts currently held by Republicans. They asked voters to choose between their current representative and a generic Democrat (data as PDF). Here are the margins they got, plotted against last November’s election result:

The swing was toward Democrats for 23 races (below the red diagonal) and toward the Republican for 1 race (above the diagonal). The key piece of information is the gray zone. If more than half the points are in that gray zone, then that predicts a swing of >6% and a Democratic takeover. Currently, 17 out of 24 points are in the gray zone.

Individually, the district-by-district swing is quite variable, +4% to -23% (where + indicates a swing toward Republicans). But the average is clear, -10.9+/-1.5% (mean+/-SEM). That predicts a national popular-vote margin of D+12.0%.

Since the election is over a year away, it is hard to predict how this will translate to future seat gain/loss. If the election were held today, Democrats would pick up around 30 seats, giving them control of the chamber. I do not expect this to happen. Many things will happen in the coming 12 months, and the current crisis might be a distant memory. But at this point I do expect Democrats to pick up seats next year, an exception to the midterm rule.

Note that in these calculations I did not even include the worst of the news for Republicans. In a followup series of questions, PPP then told respondents that their representative voted for the shutdown. At that point, the average swing moved a further 3.1% toward Democrats, and 22 out of 24 points were in the gray zone. That would be more like a 50-seat gain for Democrats – equivalent to a wave election. An analyst would have to be crazy to predict that! However, it seems like mandatory information for a Democratic campaign strategist – or any Republican incumbent who won by less than 20 points in 2012.