Rep.-elect David Rivera (R-Fla.) on Friday denied receiving $500,000 in secret payments from a dog track for a company with ties to him.

The Miami Herald reported that a state's attorney's office is probing the payments, which allegedly were made in 2008 from Flagler Dog Track to Millennium Marketing, which is co-managed by Rivera's 70-year-old godmother. 

According to the Herald, most of the money was paid in 2008, when Rivera helped run a campaign backed by the dog track to help win approval for slot machines at certain gambling venues in Miami-Dade County. At the time, Rivera was a member of the Florida House of Representatives. 

The news comes before Rivera has even been seated and could cause a headache for the lawmaker-to-be who is part of the GOP's vaunted freshman class. 

Rivera won the 25th district seat of Rep. Mario Diaz-Balart (R-Fla.), who decided to run for the open seat in the more reliably Republican 21st district, which was vacated by his brother Lincoln Diaz-Balart.

In a statement to the Herald, Rivera denied accepting payments from Flagler or from Millennium, which is now called Magic City Casino. He has previously denied working for the dog track, though the Herald noted he "played a public role in supporting the pro-slots referendum campaign."

The Herald writes:

In the statement, Rivera said he was "designated by Millennium'' to work on the slots campaign after the firm was hired by Flagler, and added he has not been contacted by investigators. At the time the contract was signed, Millennium's sole corporate officer was Rivera's godmother, Ileana Medina.