On one level, the fight over O’Rourke is a fight over the legacy of Obama. The Obama veterans championing O’Rourke compare his “inspiration, aspiration, and authenticity” (in the words of Obama’s former campaign manager Jim Messina) to the 44th president’s. In a recent essay titled “The Case for Beto O’Rourke,” the former Obama aide Dan Pfeiffer declared that “the whole conversation around Beto has been eerily familiar to me, because these are the exact arguments people made to me when I told them I was considering working for Barack Obama 10 years ago.”

O’Rourke’s critics turn the analogy on its head. “Beto is a lot like Obama, true,” Bruenig acknowledges, but “it’s perhaps time for left-leaning Democrats to realize that may not be a good thing.” A recent Jacobin article called O’Rourke “Obama redux: an attractive, progressive-sounding, comforting figure” before declaring that Obama redux “would be disastrous,” given the former president’s policies on immigration, Wall Street, and war.

But the argument is about more than Obama. The people criticizing O’Rourke for taking fossil-fuel money don’t want to just prevent the Democratic Party from modeling its next presidential candidate on its last president. They want to overturn a model that has long dominated the party. Since the mid-20th century, Democrats have generally treated corporations as legitimate participants in the political process. Today, for the first time since the dawn of the Cold War, a powerful faction within the party wants to treat them as ideological adversaries instead.