From ABC:
With the clock running out on a new US-Russian arms treaty before the previous Strategic Arms Reduction Treaty, or START, expires on December 5, a senior White House official said Sunday said that the difficulty of the task might mean temporarily bypassing the Senate’s constitutional role in ratifying treaties by enforcing certain aspects of a new deal on an executive levels and a “provisional basis” until the Senate ratifies the treaty.
All the links and commentary by the Anchoress over at First Things.