National Polls, District Information, and House Seats: Forecasting the 2014 Midterm Election

This article presents a forecast of the 2014 midterm House election based on information available four to six months in advance. The approach builds on our forecasts of the 2006 (Bafumi, Erikson, and Wlezien 2008) and 2010 (Bafumi, Erikson, and Wlezien 2010a,b) midterm elections.1 We incorporate information about the national forces at work in the election, which are evident early in the election year from generic congressional polls plus the party of the president. We also incorporate information about the districts themselves, which is refl ected in their partisan predispositions and in other ways, most notably, whether the incumbent seeks reelection. To forecast the 2014 election, we simulate the national vote and district outcomes using the past as our laboratory, details about which we provide in the text that follows. Our forecast, based on information gathered 121 to 180 days in advance of the election (essentially May and June), is a nearcertain Republican hold of the House. In terms of the national vote, the most likely outcome is a Republican plurality of about 52.5% of the two-party vote. Of course, seats are what matter, and by our reckoning, the most likely scenario is a Republican majority in the neighborhood of 248 seats versus 187 for the Democrats. Taking into account the uncertainty in our model, the Republicans have about a 1% chance of losing the House. As circumstances can change during the election year, we provide guidance for updating the forecast based on new information that will become available leading up to Election Day. The expectation from our model is that the Republicans will win more seats in 2014 than they did even in their record showing in 2010, although with a lesser share of the vote than in 2010. If the forecast holds, why would a lesser voter share than 2010 yield more seats than 2010? First, unlike in 2010, it is the Republicans who hold the incumbency advantage. Seats they barely won in 2010 or 2012 are safer now with a Republican incumbent. A second factor is the reinforced Republican gerrymander following their capture of state legislatures in 2010. Still a third factor is the redistricting following the 2010 census. Because of voter migration, most newly created districts in 2012 are in Republican areas.