EDITOR’S NOTE: Each week we cross-post an excerpt from Katrina vanden Heuvel’s column at the WashingtonPost.com. Read the full archive of Katrina’s Washington Post columns here.

“Dark money” is our latest electoral scourge. A deluge of this unregulated, often undisclosed cash has flooded the 2022 primary season, influencing elections nationwide. Senate Republicans, backed by corporate lobbies, consistently block congressional action on the issue. But now, Democrats, at least, have the opportunity to clean up their own primaries.

When the Democratic National Committee gathers in Washington this week, Judith Whitmer, chair of the state party in Nevada, and more than 30 DNC members will support DNC Resolution 19, calling on the party to ban dark money in Democratic primaries.

No one can doubt that action is imperative. According to the nonpartisan research group OpenSecrets, dark money topped $1 billion in the 2020 presidential race. This year, the Wesleyan Media Project reported, nearly 60 percent of all ads in Democratic House primaries have been purchased by sources that did not disclose, or only partially disclosed, their donors.

An increasing amount of money from corporations and Republican mega-donors is spewing into Democratic primaries to defeat progressive candidates. Perhaps the most notorious example is the American Israel Public Affairs Committee (AIPAC) and its various affiliated PACs and outlets, which reportedly raised $1 million each from leading Republican super-donors Bernie Marcus and Paul Singer as part of a war chest used against progressive primary candidates. More than $2 million was poured into largely negative ads against Summer Lee, a progressive state legislator running in Pittsburgh, accusing her of being a disloyal Democrat. Lee started out as the odds-on favorite and barely survived, but other progressive women of color—including Donna Edwards in Maryland, Nina Turner in Ohio, Jessica Cisneros in Texas, and Nida Allam in North Carolina—suffered defeat amid the flood of negative ads funded by AIPAC and other outside groups.

AIPAC’s example will only swell the torrents of dark money flowing into primaries in the future. Because of partisan gerrymandering, fewer than 15 percent of congressional districts now have contested general elections. In the remainder, the primary effectively decides the winner, and since it is usually less costly than a general election, more and more deep-pocket donors will find it in their interest to intervene early. As Whitmer told The Nation, the coming “avalanche” of dark money is getting to the point where “people lose their right to choose their own candidates.”

The DNC has the authority to act. The courts have ruled that the political parties are essentially voluntary organizations with free-association rights. They can make their own rules for selecting their candidates.

A ban on dark money from outside groups won’t be easy to enforce. The Whitmer resolution calls for the party to set up mechanisms to investigate and expose the use of dark money, and to empower states to set primary rules to ensure transparency.

Likely measures could include requiring all candidates to disavow outside advertising by groups with undisclosed donors. Sanctions against contracting with campaign firms and operatives who work for groups in violation would be even more effective. Campaign advertising has become a notorious money-making racket for consultants, and endangering the flow of dough to the major advertising, consulting, and fundraising firms would have a sobering effect.

The real worry about partial campaign finance reforms—that no candidate or party can “unilaterally disarm”—doesn’t apply here. The DNC would be reforming contests among competing Democrats—and any dark-money ban would surely help curb the interference of Republican interests in those elections.

With progressives the big targets of outside money, it’s not surprising that progressive leaders have led the call for reform. Senator Bernie Sanders (I-Vt.) has formally called on the DNC to act, stating, “Dark money is dark money, whether it is funded by Republican billionaires or Democratic billionaires.” If the flood continues, Sanders argues, it will “demoralize the Democratic base and alienate potential Democratic voters.”

In June, Congressional Progressive Caucus leaders Pramila Jayapal (Wash.), Mark Pocan (Wis.), and Jamie B. Raskin (Md.) urged the heads of all three major party bodies—the DNC, the Democratic Congressional Campaign Committee, and the Democratic Senatorial Campaign Committee—to ban super PAC money in Democratic primaries, warning that “record sums of money from millionaires and billionaires have infiltrated our primaries, and…have drowned out the grassroots campaigns of working class, progressive candidates.”

The DNC convenes on Friday. Its meetings are traditionally controlled tightly from the top. The chairman—now Jaime Harrison—takes his signals from the White House. He usually holds enough proxies from DNC members who cannot attend the meeting to guarantee the outcome.

Passage of Whitmer’s resolution shouldn’t be controversial. Democrats in both the House and the Senate voted overwhelmingly for HR 1, the sweeping voting-rights bill introduced in 2021, which included strong campaign finance elements. President Biden campaigned for its passage. That bill was ultimately defeated, but now the Democratic National Committee can take action to clean its own house. It should not fail this test.