Analysis by Ballotpedia shows that the primary election victories by conservatives in Kansas is part of a larger national trend of incumbents losing primary election challenges. Kansas, however, is leading the trend, with the largest number of incumbents defeated among all the states.
In Kansas, about one-third of the incumbents who faced a primary challenger lost. That’s more than three times the number that lost in 2010, although the Kansas Senate was not up for election then as it is this year.
Ballotpedia’s article is Primary change: A rough night for incumbents, as 18 fall in Kansas legislative primaries. It holds a link to the larger study Primary Challenge: Anti-Incumbency Voting Patterns in State Legislative Elections.