Mr. Wyss, who has pledged to donate half of his money to charity, has donated hundreds of millions to environmental and conservation causes. Through his foundations, he has gradually increased his donations to groups promoting abortion rights, minimum wage increases, and other progressive causes.

He became a member of the Democracy Alliance, a club of liberal donors, and the board of directors of the Center for American Progress, a think tank in Washington that began with the support of the Democracy Alliance donors. The think tank and its sister faction have received more than $ 6.1 million from foundations affiliated with Mr. Wyss, according to tax returns.

Mr. Podesta, the founder of the Center for American Progress, has also advised the Wyss Foundation on, among other things, the hiring of the executive director of the Hub Project, Arkadi Gerney, a former official of the Center for American Progress.

The Hub Project grew out of the idea that Democrats should more effectively convey their arguments through the news media and directly to voters. His business plan, a 21-page document prepared for the Wyss Foundation in 2015, recommended that the group be “funded entirely by the Wyss Foundation to begin with,” and work behind the scenes to “make the public debate and politics dramatic to change positions of key decision makers. The plan added that the Hub project “is not intended to be the public face of campaigns”.

The Hub Project is part of an opaque network managed by Washington-based consulting firm Arabella Advisors that has channeled hundreds of millions of dollars through a number of groups that support Democrats and progressive causes. The system of political funding, which often obscures the identity of donors, is known as dark money, and the Arabella network is a leading vehicle for this on the left.

The Arabella network is similar to the operation created by the Kochs. Democrats have long criticized the Kochs and others who participated in the elusive political issues partly sparked by the 2010 Supreme Court ruling in the Citizens United case.

Arabella’s money goes through four nonprofits that serve as the umbrella structure for a number of groups, including The Hub Project. The nonprofits then pass some of the funds on to other nonprofit groups or super PACs.