A new lawsuit pushed by conservative operatives with ties to Donald Trump, right-wing power broker Leonard Leo, and a hate group could make donations to dark money groups tax-deductible. Such an outcome could further incentivize the massive surge of dark money flowing into politics, where there are already no limits on how much the rich and powerful can spend to influence elections.

Currently, most dark money donations flow through 501(c)(4) groups, or “social welfare” organizations, since these nonprofits are allowed to engage in political activities. While these donations are considered “dark” because their origins can remain secret, they are not tax-deductible. On the other hand, donations to charitable, religious, educational, and scientific groups that qualify as 501(c)(3) nonprofits are tax deductible — but these organizations are generally not allowed to dabble in politics.

But in a new lawsuit against the Internal Revenue Service (IRS), four religious groups including the National Religious Broadcasters, which represents Christian radio stations, argue that in order to express their free speech rights, 501(c)(3) organizations should be allowed to support political candidates. If successful, the lawsuit could be a big win for dark money donors who want to influence elections while remaining anonymous — since they would score tax breaks on their massive election spending.