Sen. Elizabeth Warren (D-Mass.), speaks at the Democratic Party’s state convention on Sept. 19, 2015, in Springfield. Mass. (Dave Roback/The Republican via AP)

Elizabeth Warren, collector of corporate hides, is on the hunt again.

Fresh from her triumph Tuesday over the Brookings Institution in which she forced the ouster of a corporate-backed scholar, the populist Democratic senator from Massachusetts was at Lutheran Church of the Reformation on Capitol Hill, firing up a crowd of housing activists Wednesday afternoon.

Facing the pews, with a large brass cross behind her, Warren blasted the Department of Housing and Urban Development and the Federal Housing Finance Agency, both run by Obama appointees, for selling troubled mortgages to hedge fund investors at a discount.

“These Wall Street investors made money by crashing the economy, got bailed out and now they’re back to feed at the trough again,” she said, “scooping up these loans at rock-bottom prices so that they profit off them a second time — and it is up to us to stop that!”

The activists cheered.

She scolded FHFA chief Mel Watt for postponing action on principal reduction for struggling homeowners. “Evidently there is no need for delay, no need for further study, if the government takes a loss and Wall Street makes a profit,” she said, “but it is absolutely necessary to delay if homeowners might have a chance to cut their mortgages and stay in their homes. This is wrong, and it is time to fight back!”

Her listeners, many of them Latinos and most in orange T-shirts announcing “Communities for Change,” applauded again.

“We need to get something straight: These federal agencies don’t work for Wall Street. They work for the American people,” Warren said. “HUD and FHFA could make these changes right now if they just had the courage to stand up for families instead of bowing to Wall Street.”

Warren wrapped up, and her listeners launched into a protest-rally chant: “The people united will never be defeated!” They then marched off to protest at the FHFA and to meet with Watt.

Given Warren’s record, Watt has reason for concern. After my Post colleagues Tom Hamburger, James Hohmann and Elise Viebeck reported Tuesday on letters Warren sent to Brookings protesting research by Robert Litan that was both corporate-backed and corporate-friendly, Brookings forced Litan to resign.

As Hohmann noted, Warren had previously blocked investment banker Antonio Weiss from becoming Treasury’s No. 3 official and Larry Summers from becoming Federal Reserve chairman. Hohmann wrote that the Litan episode “underscores just how terrified D.C. elites from both parties are right now about the rise of pitchfork populism.”

Maybe, but I wish they were more terrified. Yes, Republicans are frightened of the populist anger harnessed by Donald Trump — but he’s a billionaire real estate mogul. And Democrats are surprised by the populist insurgency of presidential candidate Bernie Sanders — but few seriously believe he can defeat Hillary Clinton for the nomination.

Clinton evidently doesn’t think he can, for her moves to the left (such as opposing the Keystone pipeline) have been few and incremental. Likewise, Warren’s victories, though a sign of the first-term senator’s clout, are pinpricks to an administration that’s getting what it wants on matters of much more importance to business, such as free trade. (After Warren blocked Weiss, for example, the administration simply appointed him to a “counselor” position at Treasury that isn’t Senate-confirmed.)

Sanders and Warren may have captured the energy and the enthusiasm within the Democratic Party, but they still haven’t captured the power. That’s because money wins elections, and Clinton, like President Obama, follows the money. Figures such as Warren have to waste their time fighting members of their own party who probably agree with her views but aren’t about to antagonize their corporate sponsors. For all the populists’ popularity, they are still fighting for scraps.

Five minutes before Warren’s event at the church was to kick off, the place was empty; bus-loads of activists had been stuck in traffic on I-95. Finally, enough arrived to fill half the church. Warren didn’t mix with the crowd before or after her speech, and the slight senator spoke so quietly it was difficult to hear her.

But her words were fierce. “HUD and FHFA have been lining up with the Wall Street speculators,” she said. “This should surprise absolutely nobody.”

It wouldn’t take an act of Congress to change this, or even a change in administrative rulemaking. “If they wanted to make changes, HUD and FHFA could do this this afternoon,” she said. And “what really gets my goat about this,” Warren said, is that they don’t — while “more and more families lose their homes and wind up out on the street.”

It’s a sign of some clout that Warren has Litan’s hide, and Weiss’s, and Summers’s. But if her party answered to the people rather than its donors, she’d have many more.

Twitter: @Milbank

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