In Election’s Final Days, Dark Money and ‘Gray Money’ Fund Hidden Agendas

The campaign literature that landed in Republican mailboxes in North Carolina this week was jarring. On one side was a sonogram image of a human fetus, with this message: “Her heart is beating. We all know it. Only the courageous few will protect her.” On the other side was a call to action: “You have the courage and the conviction to vote for Randall Terry.”

But the mailer did not come from supporters of Mr. Terry, a third-party presidential candidate and longtime leader in the anti-abortion movement.

Rather, the fine print showed it was the work of a nascent super PAC with the anodyne name of Civic Truth Action that was funded by millions of dollars in difficult-to-trace money linked to Democrats trying to elect Vice President Kamala Harris as the next president.

The final days of a high-stakes election are often a time of political mischief. The message pushed by Civic Truth Action — purportedly to help Mr. Terry but aimed at siphoning votes from former President Donald J. Trump — may be among the most cynical. But it is far from unique. Across the country, supporters of Ms. Harris and Mr. Trump are taking advantage of a patchwork of lax laws that allow partisans to funnel millions of dollars through daisy chains of opaque entities into hard-hitting campaign tactics, all to try to sway the tiny slice of swing-state voters who could make the difference.

Campaign operatives and donors have long deployed creative accounting to mask the flow of money into politics. But in the decade and a half since the Supreme Court’s Citizens United decision paved the way for unlimited spending on political advertising, it has become particularly difficult to follow the big-money flow in the weeks before Election Day, despite the majority opinion’s assertions that “prompt disclosure” of political spending would enable voters “to make informed decisions.”

“Now it’s sort of undeniable that the court was wrong with those predictions,” said Ian Vandewalker, a lawyer at the Brennan Center for Justice, a progressive nonprofit that works to reduce the influence of big money in politics. Mr. Vandewalker published an analysis this week of the increase in difficult-to-trace funding to super PACs. “The ability to hide funding for those types of things is attractive for people who want to engage in dirty tricks,” he said in an interview.