Sen. Jodi Ernst (R-IA) is running such a terrible campaign. She really made Iowa in play for the Democrats. She is the Mark Udall (D-CO) of the 2020 election.
Kansas might surprise people. The two top Republicans; Dr. Roger Marshall and Kris Kobach are being out-raised by the Democrat Dr. Barbara Boiler, even when you combined their money. If Kobach wins the primary, Dems could easily take Kansas. Kobach was rejected by KS voters in the 2018 gubernatorial election.
It's also important to note the Boiler was a Republican up until 2018, so she does have moderate blood and Republican roots.