Prominent progressive and mayor of New York City, Bill de Blasio thinks Hillary Clinton has the toughest plan for Wall Street reform. | Getty Progressive New York mayor backs Clinton’s Wall Street package De Blasio helps the Democratic front-runner preempt Bernie Sanders’ financial reform plan.

As Bernie Sanders prepared to deliver a speech on Wall Street reform, New York City’s progressive mayor, Bill de Blasio, endorsed Hillary Clinton’s financial proposals instead.

“Having studied all the Wall Street reform proposals, I firmly believe Hillary Clinton has put forward the toughest, farthest-reaching plan of anyone running for President,” de Blasio said in a statement to POLITICO. “She would not only go beyond Dodd-Frank to ensure the needed authority exists to break up or downsize banks that are too large, but she also imposes new constraints on activities in the shadow banking sector, which is too often overlooked.”


He added: “Hillary Clinton’s plan confronts risk-taking wherever it occurs, from investment and commercial banks to insurance firms to hedge funds. Her plan goes the farthest to crack down on the true causes of the last financial crisis, and to prevent the next one.”

Wall Street reform has been the backbone of Sanders’ presidential bid and driven much of his grassroots, progressive appeal. His campaign sees the issue as his best lane to winning the primary, and has tried to represent Clinton as a politician too close to the financial industry she represented as a senator from New York.

In Sanders’ speech in Manhattan, he is expected to announce an agenda to break up the “too big to fail” banks in his first year in office, and to reinstate the Glass-Steagall Act, which separated commercial and investment banking activities.

A nod of approval from de Blasio, who has tried to position himself as a national progressive standard bearer, appears an attempt to redeem himself with Clinton -- he spent months last year holding out on endorsing her campaign and flirting with Sanders, despite a personal tie to the candidate whose 2000 Senate race he managed. On Tuesday, he helped to position her to the left of Sanders on one of the major planks of the insurgent 2016 contender’s campaign and deliver a blow to Sanders.

De Blasio’s support was just one part of the Clinton campaign’s preemptive strategy to undercut Sanders’ Wall Street pitch. On Monday, the campaign's chief financial officer Gary Gensler urged Sanders to support Clinton's efforts to monitor the financial industry.

“Senator Sanders has so far taken a hands-off approach to some of the riskiest institutions and activities in our economy, which were among the biggest culprits during the 2008 crisis,” Gensler, a former top Wall Street regulator, said. “Senator Sanders should go beyond his existing plans for reforming Wall Street and endorse Hillary Clinton’s tough, comprehensive proposals to rein in risky behavior within the shadow banking sector.”

In his address, Sanders is expect to state that “a handful of huge financial institutions simply have too much economic and political power over this country,” according to an excerpt of his speech released by the campaign.

But progressive watchdogs said when it comes to economic policy, personnel is policy.

"There is an air of unreality about debates about which candidates' legislative proposals to augment Dodd-Frank are tougher on Wall Street and the excesses of `shadow banking,’” said Jeff Hauser, director of the Revolving Door Project. “Congress will have enormous say in whether Dodd-Frank is improved or degraded. What the president can control is whom they would appoint, which is why financial reformers tend to be more curious about whether current financial sector heavyweights would be nominated for key positions like Treasury Secretary.”