Senate Observations: Placing 2018 In the Context Of Upper Chamber Elections Since 1913 By Geoffrey Skelley
From 1914 to 2016, presidential cycles featured a higher rate of straight-ticket outcomes than midterm elections, with 74% of presidential-Senate results going for the same party in presidential years. Midterm cycles showed more splits, with just 61% of presidential-Senate results won by the same party. In 21 of 25 midterm cycles that followed a presidential election in the 1913-2016 period, the share of split-ticket presidential-Senate results increased compared to the share in the previous presidential cycle.