There are 1,064 open seats in this year’s state legislative elections, 17% of all 6,137 seats up for election. That is below the average of 19% in each cycle since 2010. Looking only at previous midterm election years since 2010, that average was 20%.

An open seat is where no incumbent filed to run, meaning it is guaranteed to be won by a newcomer. Ballotpedia uses the number and percentage of open seats to help determine the overall competitiveness of an election cycle. A greater number of open seats guarantees more newcomers entering legislatures and typically results in more candidates running for office. A smaller number of open seats guarantees fewer newcomers and typically results in fewer candidates running for office.

Across the 46 states holding state legislative elections this year, 449 Democrat-held seats are open, 610 Republican-held seats are open, and five independent or minor party seats are open. That is 6% below average for Democrats and 2% below average for Republicans. For independent and minor party seats, that ties 2010 for the record low.

Overall, this year’s 1,064 open seats are below the average of 1,129 each year since 2010. Among midterm years since 2010, this year has the second-fewest open seats: in 2014, there were 1,019 open seats.

In three states, less than 5% of the seats up for election were open this year – North Carolina with 4.7%, Pennsylvania with 3.5%, and South Carolina with 4.8%. In five states, more than 30% of the seats up for election were open – Maine (37.1%), Missouri (34.4%), Montana (30.4%), Nebraska (50%), and Wyoming (30.8%).