Nearly all the senators left the Capitol for the Christmas holiday last week, but Democrats are keeping the Senate in session to block President Bush from making any recess appointments -- a constitutional mechanism that allows the president, during congressional recesses, to fill top government posts for up to one year without Senate confirmation.

Sen. Jim Webb, D-Virginia, opened and then immediately gaveled the Senate session to a close. He spent 57 seconds in the chamber.

Senate Majority Leader Harry Reid, D-Nevada, announced December 19 that he would keep the Senate open with a series of "pro forma" sessions through mid-January.

Similar sessions were conducted over the Thanksgiving recess.