President Donald Trump has suddenly grown interested in his former campaign manager's role in steering government contracts.The 79-year-old president has been peppering aides with questions in recent days about longtime adviser Corey Lewandowski, who had been acting as de facto chief of staff to recently fired Homeland Security Secretary Kristi Noem, and his involvement in a controversial $220 million advertising campaign, reported NBC News.“He’s mentioned the ads several times,” said a senior White House official.Lawmakers grilled Noem last week about the ads, and Trump admitted he "wasn't thrilled" she had testified that he signed off on the campaign. He reassigned her shortly afterward.But now three sources said he's turned his attention to Lewandowski’s role in awarding government contracts.Lewandowski categorically denied Monday to NBC News that he had made any money – "zero, not one penny" – from DHS contracts, but the president is suspicious."Corey made out on that one," Trump told advisers last week, according to another senior White House official.The ads showed images of Noem on horseback musing about the American dream and promising crackdowns on undocumented immigrants. Lewandowski told NBC News that he had spoken to the president in each of the three days before the DHS secretary was fired.“Since I’ve known the guy for 11 years, I think it’s fair to say if he had a concern about something I was doing, he would raise it,” Lewandowski said, adding that he had not yet decided whether to leave DHS with Noem on March 31.Democratic senators have launched an investigation into three businesses – Safe America Media, the Strategy Group and People Who Think – that won DHS contracts to produce the ads and their connections to Noem."The Strategy Group is run by Ben Yoho, the husband of former DHS spokeswoman Tricia Mclaughlin," NBC News reported. "[The senators] asked the three businesses to provide documentation of their agreements with DHS, which companies they subcontracted with and whether they had deals in place with Lewandowski."