Fourteen states will be represented by a single party on Capitol Hill – seven Democratic and seven Republican; one party controls all but one seat in 13 other states.
Each of the Top 5 and eight of the Top 10 states which have most frequently elected U.S. Senators from a party other than the sitting president are located in the Midwest; five host contests in 2018.
Nine state delegations currently have junior senators who are older than its senior senator.
There is a good chance as many as six states could have two female major party nominees for the office – doubling the previous record for an election cycle.
Thirty-one of 175 specials conducted since 1913 have been held outside of November with just 22 during odd-numbered years.
Only one of the 73 Republican U.S. House members from Trump states with Democratic US Senators on the 2018 ballot has mounted a challenge.
An average of seven senators have retired from the chamber each cycle during the past quarter-century; no incumbent up for reelection next year has yet closed the door on a 2018 bid.
The 10 Trump states with Democratic incumbents have voted for senate nominees from the opposing party of the sitting president 62 percent of the time over the last 50 years.
The Republican Party’s hold on every congressional seat could increase from nine to 12 states after the 2018 cycle.
At least one first-term incumbent has been defeated in 48 of the 52 election cycles during the direct election era.