Schweitzer's theoretical coalition here seems incredibly awkward, and a lot of the Democratic primary voters he'd probably appeal to are Clinton fans. I just don't understand what groups he'd consolidate in theory, and certainly not when he says stuff like this.
He is trying for working class/rural Dems + people who disapprove of Obama from the left. That is a very tough needle to thread. But of course Obama ran the same anti-establishment strategy, but with affluent/suburban Dems + people who disapproved of (Bill) Clinton from the left and it worked out for him. He is clearly betting that Obama will be in Bush 2008 territory by the 2016 primary. Think of how Bryan disowned Cleveland and won the nomination in 1896. Same idea.
Of course, the nomination wouldn't be very valuable if Obama was indeed in Bush 2008 levels of popularity.