Five sources told Politico that President Donald Trump is expected to nominate Nielsen, currently the White House's Principal Deputy Chief of Staff, as soon as Wednesday. Neither the White House nor Nielsen responded to requests for comment, however, and sources cautioned against jumping to conclusions.
Before working under Kelly while he was secretary, Nielsen worked in one of DHS's agencies, the Transportation Security Administration (TSA), and served former President George W. Bush's Homeland Security Council.
Nielsen is a cybersecurity expert but joined the White House to help Kelly when he became Trump's chief of staff in July.
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