“He’s a low-key guy who fits the [John] Kelly mold of a buttoned-down, process-oriented pro,” said a senior administration official. “He’s been in the White House since early on so knows the dynamics.”
Carroll would be the third person to serve as second in command to the White House chief of staff in the 10 months since the president took office.
Nielsen, a close ally of chief of staff John Kelly, appeared before the Senate earlier this week for her confirmation hearing to become Homeland Security secretary. The full Senate has yet to vote on her nomination.
The move to replace Nielsen is described as part of a broader shake up in the works, sources tell ABC News.
There have been discussions to possibly move another Deputy Chief of Staff, Rick Dearborn, out of the West Wing and into another agency – possibly the Department of Commerce. Three senior administration officials said the role being discussed for Dearborn would be deputy secretary at the Commerce Department but a final decision has not been made.
The news was first reported by Politico.
Dearborn, a longtime aide to then Senator Jeff Sessions, played a big role in the Trump campaign’s policy arm in addition to the eventual presidential transition plans.