Sen. John Cornyn’s campaign said it off-loaded more than $15,000 in illegal donations from former University of Texas Regent James Dannenbaum on Wednesday. The action came almost two months after the illegal donations were discovered and a day before MJ Hegar, one of his Democratic challengers, filed a complaint with the Federal Election Commission over the delay.

Federal law requires campaigns to send illegal donations to the Treasury Department or refund the payment “within thirty days of the date on which the illegality is discovered,” but in a Tuesday letter to the federal attorneys investigating the payments, Cornyn attorney Jason Torchinsky wrote that the campaign was told to “wait to disgorge” the money by the U.S. attorney’s office.

The letter also says the committee “remains ready to disgorge” all the illegal money but it needs to know the exact amount of money to send to the Treasury and the names of the people who donated the money.

The illegal donations came to light last November, when Dannenbaum, a prolific Texas Republican donor, pleaded guilty to making illegal campaign contributions in the name of others to candidates for president, the U.S. House and Senate. Dannenbaum, who at the time was president and CEO of Dannenbaum Engineering, funneled campaign donations through his engineering company’s employees, which he and a former employee reimbursed using company funds, according to the plea agreement.

The day before Torchinsky’s Tuesday letter, Hegar’s campaign sent a news release asking “was Senator Cornyn ever planning to return the illegal money or is he going to continue breaking federal election law?”

Torchinsky wrote that the federal attorney’s request “has become the source of misleading political attacks in the media from entities unaware of how this process works” in his Tuesday letter.

Thursday evening, Hegar’s campaign filed a complaint with the FEC alleging Cornyn had “violated federal election law.”

“If Senator Cornyn thinks he can accept illegal campaign contributions, and then lie about returning them, he has another thing coming,” Hegar said in statement with the release.

U.S. attorneys replied to Torchinsky’s letter Wednesday morning with the information requested, and $15,400 was disgorged by the campaign Thursday morning, before Hegar’s complaint was filed, a Cornyn campaign spokesman said.

Court records do not name any of the candidates that benefited from the scheme, but Federal Election Commission records show Cornyn is the only Senate candidate who received donations from Dannenbaum and his employees around the time of the illegal payments. Court documents also state none of the candidates or committees involved were aware of the scheme.

At the time of the discovery, Cornyn campaign manager John Jackson said the funds would be returned to the Treasury and the campaign was cooperating with the U.S. attorney’s office.

“We take great strides to ensure all contributions are proper and follow the law,” Jackson said.

Hegar’s campaign continued to hit Cornyn over the delay on Friday, calling Cornyn’s statements “damage control.”

“Nothing they say will change the facts,” Hegar spokeswoman Amanda Sherman said. “Senator Cornyn accepted an illegal donation, said he would return it, and when he failed to do so broke campaign finance law. It’s interesting that just hours after our campaign filed an FEC complaint they suddenly knew exactly how much money they had to return and claimed to have done so.”