State legislative incumbents are retiring at a lower rate, facing primaries at a higher rate in 2026
In the 31 states where we have completed an analysis of all available candidate-filing data for state legislative elections, an average of 26.5% of incumbent state legislators are running in contested primaries this year — the second-highest since 2010. The 17.4% average of open seats is the second-lowest since 2010.
Percentage of incumbents facing primary challengers
A larger share of incumbents face primary contests on average this year compared to previous years. That’s largely due to an increase in the percentage of contested incumbents in Republican trifecta states, up 5.5 percentage points from the 2010 to 2024 average. Meanwhile, incumbent contests are up less than one point in Democratic trifecta states and down three points in states with divided governments.
Open seats, or incumbents not running for re-election
Across the 31 states, an average of 17.4% of state legislative seats up for election this year have no incumbent running. That's down from the historical average of 19.9%, and the second-lowest since 2010. Only 2020 was lower, with 15.3%. Twenty-two of the 31 states are below their own historical average for open seats.
Percentage of primary elections with more than one candidate
This year, an average of 22.5% of possible primaries are contested across the 31 states, 0.7 percentage points higher than the historical average of 21.8%. While the states are not far from the average number of contested primaries collectively, there are a handful of noteworthy up- and downswings.
Three states are running more than eight percentage points above average: Indiana (+10 points),
North Dakota (+9 points), and South Dakota (+14 points). Two states are running more than eight percentage points below average: Maryland (-11 points) and Michigan (-10 points).
Five Republican state legislative supermajorities and three Democratic ones are highly exposed to breaking in 2026
In eight states holding legislative elections this year, fewer than 5% of seats would need to change party control to break an existing supermajority. We call those state supermajorities highly exposed to breaking. If a majority party loses its supermajority, its members lose the ability to override a governor's veto without votes from the minority party.
The Democratic supermajorities in California, Connecticut, and Delaware were rated highly exposed to breaking, because Democrats are fewer than five seats above the supermajority threshold in at least one of those states' legislative chambers.
The Republican supermajorities in Florida, Kansas, Missouri, Nebraska, and South Carolina were rated highly exposed to breaking, because Republicans are fewer than five seats or less than five percent above the supermajority threshold in at least one of those states' legislative chambers.
There are currently 27 state legislative supermajorities: 19 Republican supermajorities and eight Democratic supermajorities. The remaining 23 states have no supermajority.
The average state constitution has been amended 130 times
State constitutions are amended far more than the U.S. Constitution — 130 times on average. Louisiana has had 11 state constitutions, more than any other state, and Alabama's is the longest in the country at 338,000 words.
In the June 24 episode of Office Hours, Ballotpedia founder and CEO Leslie Graves joined host Norman Leahy to discuss state constitutions, why they changed far more often than the U.S. Constitution, and how these documents reflect our priorities and expectations at different levels of government.
A state constitution is the governing document of a U.S. state, establishing the structure of state government and guaranteeing certain rights like the U.S. Constitution does at the federal level. Some states have had multiple constitutions, and since each state drafts its own, there is great diversity among them, though all share some basic concepts.
Twenty states have had one state constitution since statehood. On average, states have had between two and three constitutions since statehood.