Luckily, however, U.S. House elections aren’t the only special elections that have taken place this year. Since Trump took office, voters have gone to the polls 24 times1 in 13 states to fill vacancies in their state legislatures — giving us a data set that is robust enough for us to start identifying patterns. And the results in these races echo the returns from Kansas and Montana: Democrats have overperformed almost everywhere.2
Since Jan. 20, Democrats have won 12 special legislative elections, and Republicans have won 11.3 But because so many special elections take place in safe districts, win-loss records can only tell you so much. Instead, you’re better off comparing their final results to the district’s baseline partisanship, which FiveThirtyEight measures using a weighted average of the last two presidential election results4 as calculated by Daily Kos.5 And in the 15 special legislative elections to pit at least one Democrat against at least one Republican,6 12 have seen a net swing toward the Democrats.