The question is whether the Senate can be flipped, and it depends on the POTUS candidate while holding the House. Turn-out must be by proportion more than in 2016 since the Electoral College requires certain swing states to be won by much larger margins in 2020.

Basically, the tipping point for Senate control shifts from North Carolina to Iowa, a state where Sanders is currently down like 5 pts against Trump. — Ethan C7 🐋 (@ECaliberSeven) February 27, 2020

Aside from the phenomenon of ticket-splitting the above chart is interesting in comparison to the analysis of flippable Senate seats.

www.dailykos.com/… Safe D Likely D Lean D Tossup Lean R Likely R Safe R DE (Coons) MN (Smith) CO (Gardner) AZ (McSally) GA-A (Perdue) AL (Jones) AK (Sullivan) IL (Durbin) NH (Shaheen) MI (Peters) GA-B (Loeffler) IA (Ernst) AR (Cotton) MA (Markey) ME (Collins) KS (OPEN) ID (Risch) NJ (Booker) NC (Tillis) TX (Cornyn) KY (McConnell) NM (OPEN) LA (Cassidy) OR (Merkley) MS (Hyde-Smith) RI (Reed) MT (Daines) VA (Warner) NE (Sasse) OK (Inhofe) SC (Graham) SD (Rounds) TN (OPEN) www.dailykos.com/…

If Bernie made it to the convention with a plurality of the delegates but not a majority and was denied the nomination, it would rip the party apart, plain and simple. https://t.co/SXEXEd3ka5 — Charles M. Blow (@CharlesMBlow) February 27, 2020