Liberal groups aligned with Sen. Elizabeth Warren (D-MA) are pushing supporters to help in Warren’s fight to prevent banker Antonio Weiss from becoming undersecretary of the Treasury for domestic policy. And they are drawing a hard line in the sand.

Over the weekend Robert Cruickshank, the senior campaign manager for Democracy for America, wrote an email to supporters that began “Wall Street is out to destroy Sen. Elizabeth Warren.”

“She really struck a nerve when she came out against the nomination of Antonio Weiss, an investment banker who is helping Burger King avoid paying its fair share of taxes, to an important Treasury Department post,” Cruickshank wrote in the email.

It ended with the bolded line “The Antonio Weiss nomination has become a crucial moment in the fight for the future of this country. We cannot let Wall Street win.”

On Monday another liberal-aligned organization, the Progressive Change Campaign Committee (PCCC) sent out an email to supporters saying that Weiss’s nomination “is a big mistake.” The email continued (emphasis PCCC’s):

Antonio Weiss made millions by helping American companies like Burger King move their headquarters overseas to escape taxes. This cost us money that could be used to create jobs.

Even worse, his investment bank has said it will pay him over $20 million if he takes this job at Treasury. What are they expecting in return?

Elizabeth Warren is courageously opposing the nomination, and a big grassroots campaign is mobilizing behind her.

Nominees for under secretary of the Treasury for domestic finance don’t usually get quite as much attention as Weiss’ has — especially among liberal organizations since Weiss has donated significant sums to the Democratic Party. But Warren and one or two other liberal senators argue that Weiss is too close to Wall Street and his involvement in a merger between Burger King and Tim Horton’s shows how he would only continue the economic policies Warren and others have been railing against.

On Sunday night in a closed meeting with about 50 top donors in the Boston area Warren reportedly reiterated some of her criticisms of Weiss. Politico reported that, according to an attendee at the event, Warren said that “at some point we have to recognize that there are other types of experience besides working on Wall Street that qualify people to do” the jobs like the one for which Weiss is nominated.