Jeff Merkley is my sleeper prediction. He has some similar beats to 2016 Bernie: no one knows about him, is left of the majority of dems, has a relatively safe seat in Oregon, history of regularly voting against the majority of the senate for things like military budgets, is a socdem. He tried to run in 2020 but wasn't able to convince the Oregon state government to allow him to run for senate and president at the same time.

Though I have my doubts that he has the energy or charisma to rally up the support. Otherwise, I see Pritzker as fitting the role.