Marco Rubio is a lucky man.

The Florida senator and Republican presidential hopeful has gotten nearly $8.5 million in television advertising promoting his candidacy run in early states and he hasn’t paid a dime for it.

The ads have come courtesy of the Conservative Solutions Project, a 501(c)(4) organization that is supposed to use its money to promote social welfare causes. For that reason, the group is not required to disclose its donors.

But the only cause Conservative Solutions Project appears to be promoting is Rubio’s, which would appear to be a violation of Internal Revenue Service (IRS) regulations. In fact, the group is the second-biggest spender in the presidential race. In an editorial, The New York Times called Conservative Solutions Project’s tactic “one of the most brazen” abuses of the political finance system.

Citizens for Responsibility and Ethics in Washington, along with Campaign Legal Center and Democracy 21, have filed complaints with the IRS and have urged the Justice Department to investigate Conservative Solutions Project.

“The Conservative Solutions Project is flaunting the tax laws and flaunting the interests of the American people by using its improper claim of nonprofit tax status to keep secret the donors financing its campaign activities,” Democracy 21 president Fred Wertheimer said in a statement, according to the Associated Press.

Conservative Solutions Project appears to be counting on the fact that any accounting of its status won’t happen until after the election, when few will care and Rubio will either be defeated or sitting in the Oval Office, where he could quash an investigation.

“As long as you know who’s behind the money and how much they’re giving and where they’re spending it, I think that’s the sunlight that we need,” Rubio told a New Hampshire voter this year regarding secret campaign financing.

Wrote the Times editorial writers regarding that statement: “He should tell this to his allies running Conservative Solutions. If he does not, someone in the next debate should ask him who has been paying for his TV spots.”

-Steve Straehley

To Learn More:

Marco Rubio Breaks New Ground in Dark Money (by Richard Skinner, Sunlight Foundation)

Senator Rubio’s Stealthy Donors (New York Times)

Marco Rubio’s Operation is Relying on Unprecedented Dark Money Spending (by Andrew Propok, Vox)

Second Complaint Lodged Against Pro-Rubio Secret Donor Group (by Julie Bykowicz, Associated Press)

New Non-Profit Tied to Jeb Bush Campaign Opens Floodgates to More Dark Money (by Noel Brinkerhoff and Steve Straehley, AllGov)

Will Secret Donors Dominate the Upcoming Election Season? (by Steve Straehley, AllGov)

Biggest Dark Money Spender in 2014 Elections: U.S. Chamber of Commerce (by Noel Brinkerhoff, AllGov)