Patty Murray(D-WA) is running for re-election in 2022. However in 2028, Murray-D could retire after 6 terms in the US Senate. Murray's successor could be Attorney General Bob Ferguson- assuming he does not run for Governor in 2024. US Representatives Suzan Delbene-D, Pramilla Jayapal-D, Kim Schrier-D, or Marilyn Strickland-D.
Dianne Feinstein(D-CA) US Senate seat is up for re-election in 2024 and Feinstein-D will probably retire in 2024 at the age of 91. Feinstein's successor could be Treasurer Fiona Ma or Lt Governor Eleni Kounalakis.
Richard Durbin(D-IL) US Senate seat is up for re-election in 2026 and Durbin-D will probably retire in 2026 at the age of 82. Durbin's successor could be Governor JB Pritzker- assuming he does not get a cabinet position in the Biden/Harris administration, Lt Governor Juliana Stratton- assuming she does not run for Governor, Attorney General Kwame Raoul- assuming he does not run for Governor, Comptroller Susana Mendoza- assuming she does not run for Governor, and Treasurer Mike Freirichs- assuming he does not run for Governor. The IL US House Members that could run for statewide office are Marie Newman(IL-3) or Raja Krishnamoorthi(IL-8).