Meanwhile, no Republican senators are up for reelection in states that Biden won. Looking at the initial 2024 Senate map, the most vulnerable Republican incumbent appears to be Rick Scott of Florida. But Florida is no longer a battleground state after GOP Gov. Ron DeSantis and GOP Sen. Marco Rubio were just reelected by close to 20 points.
It’s the first time in recent memory that one party doesn’t have a single vulnerable Senate seat on the initial battlefield. In initial ratings from Inside Elections and The Rothenberg Political Report going back to the 1994 cycle (when the Rothenberg Report started releasing formal ratings), each party has had at least two vulnerable seats. The battlefield includes any seats not rated as Solid Republican or Solid Democratic.
The closest recent comparison is probably 2014, when Democrats defended nine seats rated as initially vulnerable: Alaska, Arkansas, Louisiana, Massachusetts, Montana, New Hampshire, North Carolina, South Dakota and West Virginia. Republicans had two vulnerable seats (Kentucky and Maine), although they were rated as Likely Republican, on the outer ring of the battlefield.
That discrepancy was one factor in a difficult cycle for Democrats as Republicans gained nine Senate seats. This cycle, Republicans need a net gain of two seats for a majority, or they can control the Senate by gaining one seat and winning the White House.
Early in the 2016 cycle, Republicans were defending 10 vulnerable seats (Arizona, Florida, Georgia, Illinois, Iowa, New Hampshire, North Carolina, Ohio, Pennsylvania and Wisconsin).