The nation will witness a major US Senate turnover in the upcoming 120th Congress (2027-2029).
This would be due to retirements, primary defeats, potential election defeats, and 4 Senators running for Governor.
For now, the following is certain:
The following 11 US Senators are retiring:
Republican Tommy Tuberville of Alabama, running for Governor
Democrat Dick Durbin of Illinois
Republican Joni Ernst of Iowa
Republican Mitch McConnell of Kentucky
Democrat Gary Peters of Michigan
Democrat Tina Smith of Minnesota
Republican Steve Daines of Montana
Democrat Jeanne Shaheen of New Hampshire
Republican Thom Tillis of North Carolina
Republican Alan Armstrong of Oklahoma, appointed temprarily to replace Markwayne Mullin
Republican Cynthia Lummis of Wyoming
The following two US Senators were defeated in primaries:
Republican Bill Cassidy of Louisiana
Republican John Cornyn of Texas
The following seven US Senators are endangered for reelection:
Republican Dan Sullivan of Alaska, challenged by Mary Peltola
Republican Ashley Moody of Florida, challenged by Alex Vindman
Democrat Jon Ossoff of Georgia, challenged by Republican nominee
Republican Susan Collins of Maine, challenged by Graham Platner
Democrat Ed Markey of Massachusetts, challenged by Seth Moulton in primary
Republican Pete Ricketts of Nebraska, challenged by Independent Dan Osborn
Republican Jon Husted of Ohio, challenged by former Senator Sherrod Brown
Likely gains for Democrats seem possible or likely in
Alaska, North Carolina (open seat), Maine, Ohio, and with outside chances in Texas (open seat), Iowa (open seat), Montana (open seat), and Florida.
But Republicans have possibilities in Georgia, Michigan (open seat), and New Hampshire (open seat).
Also, the following US Senators are running for Governors of their states, and if elected, would resign from the Senate, and a replacement would be appointed or elected:
Democrat Michael Bennet of Colorado
Democrat Amy Klobuchar of Minnesota
Republican Marsha Blackburn of Tennessee
IF all of the above were to occur, the maximum number of new US Senators, either by election or appointment for replacements, could reach the mid 20s in number.
Imagining about 20 new Senators as a minimum, is very likely to occur!