So far this year, 121 state legislative incumbents—20 Democrats and 101 Republicans—have lost to primary challengers.

Across the 26 states that have held primaries, 4.6% of incumbents running for re-election have lost, more than in previous cycles.

In addition to earlier primaries, these totals include initial results from primaries in Colorado, Illinois, New York, Oklahoma, and Utah and primary runoff results in South Carolina. Incumbents defeated in those states so far include:

• Three Republicans in Oklahoma; and,
• One Democrat and two Republicans in Utah, adding to three Republican incumbents defeated in conventions there last April. Those convention defeats are included in primary defeat totals.

No incumbents have lost in Colorado or Illinois. Additionally, in New York, no incumbents have lost so far, though only the state Assembly held primaries on June 28. The Senate will hold its primaries in August.

This year, Republican incumbents have lost at a higher rate than Democrats. Of the 1,531 Republican incumbents who filed for re-election, 101 (6.6%) have lost to primary challengers. For Democrats, 20 of the 1,101 who filed for re-election (1.8%) have lost.

But fewer Democratic incumbents are facing primary challengers than their Republican counterparts. Around 21% of Democratic incumbents who filed for re-election faced contested primaries compared to 32% for Republicans.

In these 26 states, 2,634 incumbents filed for re-election, 711 of whom (27%) faced primary challengers.

Twenty-eight of these 121 incumbent defeats (23%) were guaranteed due to redistricting.When states redraw legislative lines, incumbents can oftentimes end up in a new district with other incumbents leading to incumbent v. incumbent primaries or general elections. Since, in these races, there are more incumbents running than nominations or seats available, at least one incumbent must lose.

Of the 26 states that have held primaries so far, eight have Democratic trifectas, 15 have Republican trifectas, and three have divided governments with Democrats controlling the governorship and Republicans controlling both legislative chambers. Across these 26 states, there are 3,337 seats up for election, 54% of the nationwide total.

The figures for 2022 will likely increase. There are currently 50 uncalled primaries featuring incumbents—28 Democratic and 22 Republican—and 20 primaries featuring New York Senate incumbents scheduled for Aug. 23.