The Senate left town for the year without acting on dozens of President Donald Trump's nominees, including his picks to head the Health and Human Services Department and NASA.
The Senate's lack of action returns the nominations to the White House, which will have to re-nominate them in January if Trump wants them installed.
Nominees in limbo include former pharmaceutical company executive Alex Azar to run Health and Human Services, Oklahoma Rep. Jim Bridenstine at NASA and Kansas Gov. Sam Brownback for an ambassador's post.
The nomination of former deputy national security adviser KT McFarland, tapped for ambassador to Singapore, is in doubt amid questions about her communications with ex-national security adviser Michael Flynn.
A spokesman for Majority Leader Mitch McConnell said nominees will be considered once they are resubmitted.