Sanders’ only real hope of getting back to top dog status now is to pursue a twofold strategy.

First, he needs knock the crap out of Biden for supposedly being a corporate, establishment, Democrat-In-Name-Only tool—which he and Sen. Elizabeth Warren are already trying mightily and which may or may not succeed (my bet is, it won’t dent Biden sufficiently on its own because few voters actually vote on policy and instead pick their favorite avatar and conform their views to fit what the candidate thinks—and Biden is a pretty likable guy; also few Democratic voters are as liberal as we’d all think from looking at Twitter, and some data shows Sanders might be more of a draw for more conservative voters than Biden would be). That’s been a theme in Sanders’ emailing since Biden’s entry, too.

The second component will be to capitalize on the enthusiasm and energy of the Sanders base to outwork Biden. That’s why it was interesting to receive another email, this one on Friday and signed by Sanders himself, focused on the need to raise more money to “build the organization and staff in states capable of channeling that enthusiasm into votes.” As it stands, Sanders knows he’s behind. This is the hope he can sell to his base as a counter to the well-founded fear of well-financed, much-anticipated competitor walking in and changing literally everything in a matter of hours.