Top Bidder for Tribune Newspapers Is an Influential Liberal Donor

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

He became a member of the Democracy Alliance, a club of liberal donors, as well as the board of the Center for American Progress, a Washington think tank that got its start with support from Democracy Alliance donors. The think tank and its sister political group have received more than $6.1 million from foundations linked to Mr. Wyss, according to tax filings.

Mr. Podesta, the founder of the Center for American Progress, has also advised the Wyss Foundation, including on the hiring of The Hub Project’s executive director, Arkadi Gerney, a former official at the Center for American Progress, according to people with knowledge of the arrangement.

The Hub Project came out of the idea that Democrats should be more effective in conveying their arguments through the news media and directly to voters. Its business plan, a 21-page document prepared for the Wyss Foundation in 2015, recommended that the group “be solely funded by the Wyss Foundation at the outset” and that it would work behind the scenes to “dramatically shift the public debate and policy positions of core 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 a Washington consulting firm, Arabella Advisors, that has funneled hundreds of millions of dollars through a daisy chain of groups supporting Democrats and progressive causes. The system of political financing, which often obscures the identities of donors, is known as dark money, and Arabella’s network is a leading vehicle for it on the left.

The Arabella network has similarities to the operation created by the Kochs. Democrats have long criticized the Kochs and others who have engaged in the hard-to-track political spending unleashed in part by the Supreme Court’s decision in the 2010 Citizens United case.

Arabella’s money flows through four nonprofits that serve as parent structures for a range of groups, including The Hub Project. The nonprofits then pass some of the funds along to other nonprofit groups or super PACs.