G. Elliot Morris notes 17 Republican and 11 Democratic U.S. House members have said they won’t run for re-election next year.
“Historically, the number of net retirements for each party is a pretty reliable predictor of which one will pick up seats in the U.S. House during the next midterm. The following rules are not true for every cycle, but are pretty good: (1) Whichever party has more net retirements tends to lose more seats, all else being equal; and (2) More net retirements usually translates to more seats lost.”