Vulnerable House Republican now faces an ethics investigation that could kill his chances
Congressman Rod Blum (R-IA) speaks to a crowd at a Trump rally in 2016. Image via screengrab.

The House Ethics Committee has opened an investigation into Iowa Republican Rod Blum — a congressman considered to be one of the "most vulnerable" in the House.

Roll Call reported Tuesday that the committee is looking into allegations raised by a February Associated Press report claiming Blum's top staffer was featured in a fake testimonial for a company he owned and failed to disclose on his financial disclosure forms.

Along with issuing a statement announcing its investigation, the House Ethics Committee also published a document Tuesday "clarifying" the House's guidelines on members personally endorsing or promoting "organizations, products, or services where they have a financial interest."

The report noted that the congressman called the investigation a "crusade of personal destruction" from the "radical left."

"In my case they scream ‘ETHICS VIOLATION!’ over a clerical error on a form," Blum wrote. "Once this minor error was brought to my attention, I immediately self-reported to the Ethics Committee and apologized."

Last week, Politico reported that the National Republican Congressional Committee is considering cutting off funding to "lost cause" candidates — and Blum was considered chief among them.

Over the weekend, American Ledger also reported that the Iowa Republican is allegedly a moderator of the same conspiracy-filled "Tea Party" Facebook group as Florida gubernatorial candidate Ron DeSantis.

After the report about the Facebook group was published and the AP requested comment about it, Blum tweeted the name, phone number and email address of the same reporter who wrote about his alleged ethics violation in February, Splinter reported.