If Senate Democrats do decide to reform the filibuster at the start of the 113th Congress, chances are they'll adopt Sen. Jeff Merkley's (D-Or.) proposal for a "talking filibuster."
The core idea is to make the actual filibuster more like the mythical filibuster of "Mr. Smith Goes to Washington," in which a single senator can hold the floor and block a bill's passage as long as he keeps talking.
But a lot comes down to how, specifically, that idea is implemented. Thanks to reporting from the Huffington Post's Ryan Grim, those details are starting to become clearer. Here's how the talking filibuster would work. Currently, the Senate majority must call a cloture vote to move a bill forward. If there are 60 votes for cloture, then the chamber proceeds to a 30-hour debate over the bill. After that, the bill is subject to an up-or-down vote. The system looks a bit like this:
Merkley's plan would preserve the cloture vote, and if 50 or fewer Senators support the motion, then cloture fails. But if 51 to 59 Senators support it, then the bill does not come to an up-or-down vote as long as a Senator is on the floor speaking. If at any point there is not an opposing Senator on the floor talking, then another cloture vote is triggered, which needs a simple majority to pass. Once that passes, the bill comes to the floor for final passage. Some details are left to be filled out, but it would work roughly like this:
But there are problems. The Merkley proposal does nothing to block "holds" by individual senators. Those individuals could still, by denying unanimous consent to close debate before a cloture vote is even called, hold up bills and nominations singlehandedly.
More troublingly, Merkley's proposal would allow consideration of amendments during the talking filibuster, which raises the prospect of "filibuster by amendment," wherein the minority files a huge number of amendments so that the sheer number of votes bogs down the process. Gregory Koger, a filibuster expert at the University of Miami, has raised the prospect of such a tactic as a key tool for the minority under a talking filibuster system.
There are still a number of details to be worked out. While Merkley has suggested in the past that he wants to do away with the filibuster on motions to proceed (that is, motions to even start considering a bill or nomination), the latest talking filibuster plan doesn't touch on this. The plan also does not state whether debate during the talking filibuster would have to be germane to the topic at hand. If the talking filibuster of, say, immigration reform can involve long soliloquies about One Direction, that's a lot easier for the minority than if all speeches have to be about immigration.
It's possible to craft a stronger version of the talking filibuster, one that caps the number of amendments proposed and requires all debate to be germane. That would do more to tamp down on obstruction. But even then, the Merkley plan would still allow a determined 41-vote minority to block bills and nominations. You'd need to actually eliminate the filibuster, or reduce the cloture vote requirement, or adopt a system like the one Sen. Tom Harkin (D-IA) has proposed in which the vote requirement drops over time, to prevent supermajority rule altogether.