On Wednesday, the top Republican on the House Oversight Committee, Rep. James Comer of Kentucky, fired off numerous letters to banks and the US Treasury Department to demand more information about Hunter Biden and his circle of associates, according to the Wall Street Journal, which has viewed the letters.

The probe has no Democratic support, and House Republicans have no enforcement powers. But should Republicans win House control in November, as many polls suggest, it would give them the power to hold hearings and issue subpoenas. Lawmakers involved said the requests for information are a sign of where the GOP will focus its investigative authority.

"We're definitely laying the groundwork to come out of the gate in January," said Comer, who added that the investigation will focus on whether President Biden had any links to his son's business dealings.

The Wednesday letters to several banks where Hunter Biden and family members have accounts request any possible records, documents and communications related to any potential suspicious-activity reports (SARs). In addition, Comer asked Treasury Secretary Janet Yellen for any SARs related to Hunter and James Biden, the president's brother.