While 18 months is typical for staff turnover in the White House, it comes at a perilous moment for Democrats ahead of crucial midterm elections.

“Given the complex challenges that the administration is facing, these departures are coming at an inopportune time,” said Democratic strategist Joel Payne.

Still, Payne added, “at this point in an administration, it is not abnormal to experience attrition.”

One senior administration official acknowledged that many aides are “tapped out.”

“It’s been a long few years,” the official said. “The burnout is real. It might not be the ideal time to leave with everything going on, but it’s the right time.”