U.S. Sen. Susan Collins gives two thumbs up in a speech to supporters on Nov. 3, 2020 in Bangor as it became clear that she would win her re-election race over outgoing House Speaker Sara Gideon, D-Freeport. Credit: Linda Coan O'Kresik / BDN

A large Democratic dark-money network was responsible for about $4 million in early spending in Maine’s 2020 U.S. Senate race, with one group it funded setting early attacks on Sen. Susan Collins in motion before fading as other better-funded groups came in.

The 2020 U.S. Senate race was the most expensive in Maine’s history by far, with outside spending and contributions to candidates topping $200 million, according to federal data. A small share of that came from the Sixteen Thirty Fund, a national Democratic network that does not disclose donors but has funded progressive causes in Maine before.

Connections between Sixteen Thirty Fund and several left-leaning groups in Maine were reported last year, though all of the amounts of money were not clear at the time. The nonprofit’s tax returns, filed last week and first reported by Politico, show about $4.2 million in contributions to several Maine groups in the 2019 fiscal year. It raised $140 million overall.

The bulk of that Maine spending — more than $3.8 million — went to Maine Momentum, another dark-money nonprofit that organized events and ran ads critical of Collins in 2019 and the first half of 2020. It was run by Willy Ritch, a former aide to U.S. Rep. Chellie Pingree, a Democrat from the 1st District, and worked in concert with other groups with Sixteen Thirty Fund ties including the Maine People’s Alliance, which got $200,000 from the network last year.

Maine Momentum was among the first groups to go after Collins with ads in the fall of 2019, though many other groups would join in over the next year. The incumbent Republican ultimately won reelection with 51 percent of votes after a bitter campaign with outgoing House Speaker Sara Gideon, D-Freeport.

Though Collins, Gideon and independents Max Linn and Lisa Savage frequently criticized dark money during the race, dark money from the Sixteen Thirty Fund and other groups likely accounted for less than 10 percent of the money that flowed into the Senate race. The network gave money separately to national liberal groups opposed to Collins.

Dark money refers to spending by 501(c)(4) nonprofit groups like the Sixteen Thirty Fund that eschew most donation reporting requirements by saying they are focused on issues, not elections. That means their funding sources cannot be traced to individuals, though some financial information can be gleaned via yearly tax returns.

In Maine’s U.S. Senate race, dark money spending totaled at least $12 million, according to ad data. But spending by candidates, which can be traced to individuals, surpassed $70 million as of mid-October, according to federal data.

The Sixteen Thirty Fund has emerged and grown in the last few years by mimicking an older dark-money network that was run by the conservative Koch brothers, which funded early attacks on Democratic senators. It has been the largest example of this kind of network on the left and defends its work as evening the playing field for Democratic candidates.

Because much of it happened in 2019 before other groups entered the race, the anti-Collins effort by Maine Momentum overshadowed the work of similar 501(c)4 nonprofits on the conservative the U.S. Chamber of Commerce and One Nation, which spent millions to support Collins. One Nation, which is aligned with Senate Republican leaders, spent at least $3.1 million as of mid-July to boost Collins.

Those groups were mostly quiet in the final months before the election, however, likely in part due to federal restrictions that require greater disclosure from groups that spend money close to an election, though their affiliated super PACs, such as the Democratic Senate Majority PAC and the Republican 1820 PAC and American Crossroads, were among the biggest outside spenders in the race, spending a combined more than $34 million.

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