Marco Rubio signed the letter to Iran

Here is the full list of who signed:

Senator Tom Cotton, R-AR

Senator Orrin Hatch, R-UT

Senator Charles Grassley, R-IA

Senator Mitch McConnell, R-KY

Senator Richard Shelby, R-AL

Senator John McCain, R-AZ

Senator James Inhofe, R-OK

Senator Pat Roberts, R-KS

Senator Jeff Sessions, R-AL

Senator Michael Enzi, R-WY

Senator Michael Crapo, R-ID

Senator Lindsey Graham, R-SC

Senator John Cornyn, R-TX

Senator Richard Burr, R-NC

Senator John Thune, R-SD

Senator Johnny Isakson, R-GA

Senator David Vitter, R-LA

Senator John A. Barrasso, R-WY

Senator Roger Wicker, R-MS

Senator Jim Risch, R-ID

Senator Mark Kirk, R-IL

Senator Roy Blunt, R-MO

Senator Jerry Moran, R-KS

Senator Rob Portman, R-OH

Senator John Boozman, R-AR

Senator Pat Toomey, R-PA

Senator John Hoeven, R-ND

Senator Marco Rubio, R-FL

Senator Ron Johnson, R-WI

Senator Rand Paul, R-KY

Senator Mike Lee, R-UT

Senator Kelly Ayotte, R-NH

Senator Dean Heller, R-NV

Senator Tim Scott, R-SC

Senator Ted Cruz, R-TX

Senator Deb Fischer, R-NE

Senator Shelley Moore Capito, R-WV

Senator Bill Cassidy, R-LA

Senator Cory Gardner, R-CO

Senator James Lankford, R-OK

Senator Steve Daines, R-MT

Senator Mike Rounds, R-SD

Senator David Perdue, R-GA

Senator Thom Tillis, R-NC

Senator Joni Ernst, R-IA

Senator Ben Sasse, R-NE

Senator Dan Sullivan, R-AK

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