The road to an agreement on the "fiscal cliff' in Washington may be blocked by an unexpected issue - a change in the Senate rule on filibusters.
Majority Leader Harry Reid, D-Nev., and Minority Leader Mitch McConnell, R-Ky., are at odds over the issue.
Filibusters allow an individual senator to block a bill or nomination by simply talking about it endlessly until 60 senators vote to stop it.
Reid said he just wants to make a small change to the rule so the Senate can operate more efficiently.
But McConnell accused Reid of trying to give more power to the Democratic majority.
Sen. Jeff Merkley, D-Ore., offered one proposal to change the process which would require minority opponents of a measure to actually take the floor and not just note their plans to obstruct.
Republicans believe the Democratic majority may try to usher through changes to the filibuster rules quickly when they return to Washington in January.
McConnell said they may use a procedural rule sometimes called the "nuclear option" to pass the changes with a simple 51-vote majority.
This would override the normal requirement of a 67-vote majority normally in place for rule changes in the Senate.
McConnell said if they can't agree on the filibuster rule, it will hurt their ability to work together on the "fiscal cliff."