Sanders allies disputed the import of the story, telling Politico that it was wrong to view their struggles as the fault of the candidate. “Last time, our field program was so far superior [to Hillary Clinton’s] that I think it may color people’s views,” Jeff Weaver, a top Sanders adviser, said. Now, “some of our competitors do have good field programs—Elizabeth Warren is one of them.” And another ally agreed, positing that the disappointment in New Hampshire is the byproduct of outsize expectations. “I don’t think Bernie’s doing poorly, but not as well as some people would like,” the source said.

Admittedly, Sanders set a high bar for himself as the man who first tapped into a vein of discontent on the left, and unstopping a veritable geyser of progressive energy to the shock of Clinton’s campaign. This time, however, he’s got competition to capture that energy—not just from Warren, but from Biden himself, who’s been surprisingly adept at maneuvering leftward issues like health care and income inequality, while maintaining his hold on the centrist, slightly more conservative voters of the party. But as the director of the Working Families Party told me shortly after they endorsed Warren, the only way to beat Biden for the nomination—and, ultimately, to win against Donald Trump—is to consolidate the progressive vote, and fast. “We need the time. Especially when we’re facing an opponent that is fully organized and has been campaigning, frankly, since he got elected,” said Maurice Mitchell, alluding to Trump and the RNC’s obscenely massive war chest, accumulating since the very beginning of the Trump administration.

Warren and Sanders may be ideological allies, a point underscored during the July debates, when both senators refused to attack each other and focused their firepower on centrist opponents instead. But ultimately, one of them has to make the case that they are the best person to articulate a progressive message against Trump. And that means making the case that the other person is not. “Some people are trying to position themselves in quote-un-quote Bernie’s lane,” Weaver argued to Politico. “But as the campaign goes on, people who want a bold, progressive vision for the country will come back to Bernie Sanders.” That is, unless Warren has a five-part plan to take over Bernie’s lane.

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