Senate Majority Leader Harry Reid (D-Nev.) has put Senators on notice that the chamber may be in session for several Saturdays in December.Reid hopes to spend the bulk of the month on the Senate’s health care reform bill, but the chamber also will need to complete the annual spending bills that fund the government. The current stopgap appropriations bill expires Dec. 18.Democratic aides said Reid told Senators this week of the possibility of multiple Saturday sessions, and he has been seeking to line up Members to serve as the Senate’s presiding officer on Saturdays.Though Sen. Robert Byrd (D-W.Va.) serves as the official presiding officer in his capacity as President Pro Tem, the Senate routinely establishes a rotating schedule for rank-and-file Senators to sit in the chair for a couple of hours. The task usually goes to freshman Members.Reid has pushed back his expected start time for the health care debate several times this year but has repeatedly asserted that he wanted to pass a bill before the end of this year. He is waiting for the Congressional Budget Office to produce cost estimates of the bill he hopes to bring to the floor. A Democratic source said the CBO score is not expected until the end of next week, meaning debate could begin as soon as Nov. 16. However, that would mean the bill would be on the floor only one week before an anticipated weeklong recess for the Thanksgiving holiday. Debate would resume in December.