The groups running the effort are MoveOn.org, CREDO, Progressives United, Progressive Change Campaign Committee, Social Security Works, Democracy for America (DFA), USAction, Campaign for America's Future, Center for Community Change and Rebuild the Dream. They've categorized senators on the basis of calls from their members to Senate offices and the responses they received.
The campaign is reminiscent of efforts early in the Obama administration to provide outside pressure on Democrats to support progressive priorities. Those efforts were largely abandoned after the White House vigorously objected.
"Weak-kneed" members consist of Sens. Kent Conrad (ND), Joe Manchin (WV) and Joe Lieberman (CT). Conrad and Lieberman are both retiring.
The "champions" are: Sen. Daniel Akaka (HI), Sherrod Brown (OH), Ben Cardin (MD), Al Franken (MN), Kirsten Gillibrand (NY), Tom Harkin (IA), Frank Lautenberg (NJ), Patrick Leahy (VT), Carl Levin (MI), Jeff Merkley (OR), Barbara Mikulski (MD), Jack Reed (RI), Jay Rockefeller (WV), Bernie Sanders (VT) and Sheldon Whitehouse (RI).
The rest are what the groups describe as "wavering" or "part-way there." These are the members whom they intend to apply the most pressure.
The full list: Sens. Max Baucus (MT), Mark Begich (AK), Michael Bennet (CO), Jeff Bingaman (NM), Richard Blumenthal (CT), Barbara Boxer (CA), Maria Cantwell (WA), Tom Carper (DE), Bob Casey (PA), Chris Coons (DE), Dick Durbin (IL), Dianne Feinstein (CA), Kay Hagan (NC), Dan Inouye (HI), Tim Johnson (SD), John Kerry (MA), Amy Klobuchar (MN), Herb Kohl (WI), Mary Landrieu (LA), Claire McCaskill (MO), Robert Menendez (NJ), Patty Murray (WA), Bill Nelson (FL), Ben Nelson (NE), Mark Pryor (AR), Harry Reid (NV), Chuck Schumer (NY), Jeanne Shaheen (NH), Debbie Stabenow (MI), Jon Tester (MT), Mark Udall (CO), Tom Udall (NM), Mark Warner (VA), Jim Webb (VA) and Ron Wyden (OR).
The push comes as Republicans are pressing Democrats to agree to cut entitlement spending by adopting policies such as gradually raising the Medicare eligibility age to 67, slowing the rate at which Social Security benefits grow, and other benefit cuts.