On Tuesday, independent Vermont Sen. Bernie Sanders–a socialist who votes with the Democratic Party’s left wing–let it be known that he will launch a campaign for the Democratic Party’s nomination for President on Thursday. His marks the first official challenge to former Secretary of State, New York Senator, and First Lady Hillary Clinton. Sanders is a sprightly 73 years old–roughly the same age as California Gov. Jerry Brown, who has suggested that age might be the only obstacle.

Sanders’s announcement comes at the same time as new revelations about the Clintons’ lack of transparency regarding the money raised for the Clinton Foundation and potential conflicts of interest with decisions Hillary Clinton took in office.

The Washington Post reported Tuesday that the Canadian charity tied to a Russian purchase of U.S.-based uranium assets had failed to reveal the names of 1,100 donors, violating a disclosure agreement Clinton had with the Obama White House.

The prelude to the ongoing “Clinton Cash” scandal–named after a new book by Breitbart News editor Peter Schweizer–was the revelation in March that Hillary Clinton operated her own private email server from her New York home, which she had used for official emails, in defiance of State Department policy and formal congressional requests for emails as part of ongoing investigations. The server was deleted and only a selection of the emails were turned over to the State Department.

At the time, Jerry Brown–who has still not yet endorsed Hillary Clinton–would not dismiss the scandal when asked by the Washington Post:

When asked about the recent controversy over Hillary Clinton’s use of a private e-mail account as secretary of state, Brown said he is not convinced the issue is a passing storm, as many other Democrats contend. “I don’t know that,” Brown said. “With these things, what makes a difference, you often don’t know until it unfolds because nothing is just what it is. It’s always in part of a larger context. Things unfold and things happen.”

Late last week, former San Francisco mayor–and Hillary Clinton supporter–Willie Brown said that the “Clinton Cash” scandal could prove “fatal” to her candidacy. Sanders, who warned in the past that Clinton would not fight the “billionaire class,” seems to agree–but could be too radical for voters.

Jerry Brown’s opportunity may have come.