Facebook released new information Tuesday about the political ads that appear on its site, days after a New York Times report raised concerns about the rigor of the tech giant’s method for tracking them.

Facebook’s “Ad Archive” catalogs ads about politics or “issues of national importance,” who sponsored them, and how much those sponsors have spent since May. According to the company’s analysis, since the spring, advertisers have spent more than $256 million to push political ads out to users. Facebook archived about 1.7 million political or issue advocacy ads in that time.

In order to do so, when an advertiser categorizes an ad as being related to politics or an issue of national importance, it must disclose who paid for the ad, Facebook said.

But that claim was contradicted when a Times reporter dug into who sponsored anonymous ads that called Jennifer Wexton, the Democratic candidate for Virginia’s 10th District, an “evil socialist” and depicted her alongside Nazi soldiers. The reporter uncovered a glaring loophole: Sponsors of political ads can fill in the disclaimer field with whatever text they want, even if it does not correspond to the name of the Facebook user or page, nor does the site verify that the sponsors of political ads are registered with the Federal Election Commission.

Despite its flaws, Facebook’s analysis offers an interesting snapshot of who’s spending the most for your attention. Facebook’s analysis shows as the midterm elections approached, many of the top spenders were high-profile candidates such as Rep. Beto O’Rourte in Texas and well-known advocacy groups like Planned Parenthood. But dark money groups and plain hucksters punched above their weight.

O’Rourke, who has prioritized accumulating small dollar donations and appealing to younger voters in his bid to unseat Texas Sen. Ted Cruz, tops the list with $5.4 million in Facebook ads. Still, Inside Elections with Nathan L. Gonzales rates the race Likely Republican.

The Trump Make America Great Again Committee, the joint fundraising committee the president shares with the Republican National Committee and state parties, spent $3.14 million. Unlike O’Rourke’s operation, Trump’s committee does not rely on small donors and can accept checks worth almost a half a million dollars.

Other big names logging more than a million dollars in Facebook ads included the National Republican Congressional Committee, Tom Steyer’s Need to Impeach super PAC, Planned Parenthood, Kamala Harris and NextGen Climate Action Committee, according to OpenSecrets.

Several politically active 501(c)(4)s made the list, including the Koch’s Americans for Prosperity, which took out ads making the case for cutting discretionary spending and passing a bill that targets union regulations, among other issues.

Another top spender was the “Vote No on 8” committee, which opposed a California ballot measure that would cap the profits of dialysis clinics, and is backed by major dialysis companies like DaVita, Kaiser Health News reported.

But some big spenders on ads “related to issues of national importance” appear to be vendors chiefly interested in making money. They include Concealed Online, which sells a service allowing users to apply for a concealed carry permit online, and shares an address with Premier Business Centers, a service offering co-working space and virtual offices. There’s also American AF, a T-shirt seller currently running ads for its “Donald Pump” shirt, depicting the president lifting weights.