Specifically, the latest, this link. For Dan's most recent thinking, the general link
https://mnppannex.blogspot.com/
As to Dan's latest post, the list of centrists; I'd put Kamala Harris dead center with Beto et al. and the view here is that Bullock is more a progressive and less a centrist than the other listed perps. He's been a trend setter on net neutrality, as Montana Governor he submitted a pro-labor amicus brief in Janus, and by focusing on Citizens United and money corrupting politics he's going to the essence of the problem.
He's been a more impressive state Attorney General than Harris. Taking a Montana campaign financing protective measure all the way to the Supreme Court [losing to that bunch of losers being the unfortunate outcome] while Harris was leaning on parents of truants.
As governor he had to take a realistic position facing the fact that Montana mines much coal; but his enviro cred is otherwise fine. He's been a solid advocate for public lands protections, against the exploitative forces we in Minnesota know all too well.
I like Bullock. Of the bunch listed at the Annex post, he's taller than the rest [including Harris there as the centrist she truly seems to be].