From Ballotpedia’s report on “Battleground States” U.S. Senate races:
Battleground states
The following eight battleground states were rated as battlegrounds by Inside Elections as of October 2021 and as either a toss-up, lean, or likely Democratic or Republican state by Cook Political Report and/or Sabato’s Crystal Ball. Click here for more information about Senate race ratings.
Arizona
The previous two Senate elections—held in 2018 and 2020—were both decided by 2.4 percentage points. In 2020, Mark Kelly (D) defeated incumbent Sen. Martha McSally (R) in a special election[10], 51.2% to 48.8%. In 2018, Kyrsten Sinema defeated McSally, 50.0% to 47.6%.
The two most recent presidential elections in Arizona were similarly close. Joe Biden (D) defeated incumbent President Donald Trump by 0.3 percentage points in the 2020 presidential election. Trump defeated Hillary Clinton (D) in the 2016 presidential election by 3.6 percentage points.
At the start of the 2022 election cycle, Inside Elections rated this state Battleground Democratic.[11]
Florida
In 2018, Rick Scott (R) defeated incumbent Sen. Bill Nelson (D) by 0.2 percentage points in the Senate race for Florida. In 2016, incumbent Marco Rubio won re-election by a margin of 7.7 percentage points.
The two most recent presidential elections in Florida were both decided by less than 4 percentage points. Incumbent President Donald Trump (R) defeated Joe Biden (D) by 3.3 percentage points in the 2020 presidential election. Trump defeated Hillary Clinton (D) in the 2016 presidential election by 1.2 percentage points.
At the start of the 2022 election cycle, Inside Elections rated this state Battleground Republican.[11]
Georgia
The two Senate elections held in Georgia in 2020—with runoffs taking place in January 2021—were both decided by 2 percentage points or fewer. Jon Ossoff (D) defeated incumbent Sen. David Perdue (R) by 1.2 percentage points, 50.6% to 49.4%. Raphael Warnock (D) defeated incumbent Sen. Kelly Loeffler (R) in a special election by 2 percentage points, 51.0% to 49.0%. In 2016, incumbent Sen. Johnny Isakson (R) won re-election by a margin of 13.8 percentage points.
Joe Biden (D) defeated incumbent President Donald Trump by 0.2 percentage points in the 2020 presidential election in Georgia. Trump defeated Hillary Clinton (D) in the 2016 presidential election by 5.2 percentage points.
At the start of the 2022 election cycle, Inside Elections rated this state Battleground Democratic.[11]
Nevada
The two preceding Senate elections were both decided by 5 percentage points or fewer. In 2018, Jacky Rosen defeated incumbent Sen. Dean Heller (R) by 5 percentage points. In 2016, incumbent Sen. Catherine Cortez Masto defeated Joe Heck (R) by 2.4 percentage points.
The two most recent presidential elections in Nevada were similarly close. Joe Biden (D) defeated incumbent President Donald Trump by 2.4 percentage points in the 2020 presidential election. Hillary Clinton (D) defeated Trump in the 2016 presidential election by 2.4 percentage points.
At the start of the 2022 election cycle, Inside Elections rated this state Battleground Democratic.[11]
New Hampshire
The two preceding Senate elections were split in competitiveness. In 2020, Incumbent Jeanne Shaheen (D) won re-election against Bryant Messner (R) by a margin of 15.6 percentage points. In 2016, Maggie Hassan (D) defeated incumbent Kelly Ayotte by 0.1 percentage points.
The two most recent presidential elections in Nevada were similarly split. Joe Biden (D) defeated incumbent President Donald Trump by 7.3 percentage points in the 2020 presidential election. Hillary Clinton (D) defeated Trump in the 2016 presidential election by 0.3 percentage points.
At the start of the 2022 election cycle, Inside Elections rated this state Battleground Democratic.[11]
North Carolina
Incumbent Sen. Richard Burr (R) is not seeking re-election, making this an open seat race. In 2020, incumbent Sen. Thom Tillis defeated Cal Cunningham (D) by 1.8 percentage points. In 2016, Burr won re-eelction by 5.7 percentage points.
The two most recent presidential elections in North Carolina were both decided by less than 4 percentage points. Incumbent President Donald Trump (R) defeated Joe Biden (D) by 1.3 percentage points in the 2020 presidential election. Trump defeated Hillary Clinton (D) in the 2016 presidential election by 3.6 percentage points.
At the start of the 2022 election cycle, Inside Elections rated this state Battleground Republican.[11]
Pennsylvania
Incumbent Sen. Pat Toomey (R) is not seeking re-election, making this an open seat race. In 2018, incumbent Bob Casey Jr. (D) defeated Lou Barletta (R) by 13.1 percentage points. In 2016, Toomey won re-election against Katie McGinty (D) by 1.5 percentage points.
The two most recent presidential elections were both decided by less than 2 percentage points. Joe Biden (D) defeated incumbent President Donald Trump by 1.2 percentage points in the 2020 presidential election. Trump defeated Hillary Clinton (D) in the 2016 presidential election by 0.7 percentage points.
At the start of the 2022 election cycle, Inside Elections rated this state Battleground Republican.[11]
Wisconsin
In 2016, incumbent Sen. Ron Johnson (R) won re-election against Russ Feingold (D) by 3.4 percentage points. In 2018, incumbent Sen. Tammy Baldwin defeated Leah Vukmir (R) by 10.8 percentage points.
The two most recent presidential elections were both decided by less than 1 percentage point. Joe Biden (D) defeated incumbent President Donald Trump by 0.7 percentage points in the 2020 presidential election. Trump defeated Hillary Clinton (D) in the 2016 presidential election by 0.7 percentage points.
At the start of the 2022 election cycle, Inside Elections rated this state Battleground Republican.[11]
Click on each state link for more detailed information. Ballotpedia also has a dynamic table that compares U.S. Senate race ratings, updated every five minutes, from The Cook Political Report, Sabato’s Crystal Ball, and Inside Elections.