In the politics of the United States, dark money refers to political spending by nonprofit organizations — for example, 501(c)(4) 501(c)(5) (unions) and 501(c)(6) groups — that are not required to disclose their donors. Such organizations can receive unlimited donations from corporations, individuals and unions. In this way, their donors can spend funds to influence elections, without voters knowing where the money came from. Dark money first entered politics with Buckley v. Valeo (1976) when the United States Supreme Court laid out Eight Magic Words that define the difference between electioneering and issue advocacy.
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