KEY POINTS FROM THIS ARTICLE

— A House forecasting model based on post-World War II history, the number of seats the presidential party holds going into the midterm, and House generic ballot polling can give us a good sense of what might happen in the House.

— However, one important factor that the model does not take into account for 2026 is the impact of an apparent Republican advantage in redistricting, which may effectively mean that Republicans are going into November with more seats than they currently hold.

— But even if one starts the Republicans with 10 more seats than they currently hold because of redistricting gains, the model still suggests Democrats are favored to win the House unless their lead in House generic ballot polling, now about half a dozen points in polling averages, evaporates.

Conclusions

Mid-cycle redistricting is likely to have only a minimal impact on the outcome of the 2026 U.S. House elections. Based on our simple but highly accurate forecasting model, adding the equivalent of 10 Republican districts prior to the election is only expected to reduce Democratic gains by about five seats. With an average lead of around 6 points on the generic ballot, Democrats would still be expected to gain around 23 seats in the House. To have a reasonable chance of maintaining control of the House, Republicans would need to be tied or leading on the generic ballot prior to the election.