Republican and Democratic Senate leaders appear close to a bipartisan agreement on modest filibuster reform, which is expected to include a provision that would prevent the filibuster's increasingly common use in blocking bills before they can be brought to the floor for debate.

As Politico reports, while exact details remain unclear, Senate Majority Leader Harry Reid (D-Nev.) and Senate Minority Leader Mitch McConell (R-Ky.) are expected to announce as soon as Thursday that they have come to an agreement placing new limits on the use of the filibuster, a procedural tactic available to the minority party to prevent legislation being passed by a simple majority. The Senate requires a three-fifths (or 60 out of the full 100, if all senators are present) majority to invoke cloture, a process that ends a filibuster.

In recent years, the Republican minority has used the filibuster with historic frequency, creating legislative gridlock and making reform a priority for Democrats in the current Congress. In one comical but depressingly illustrative anecdote, Sen. McConnell effectively performed a self-filibuster, after Sen. Reid called his bluff when bringing a debt ceiling related bill to the Senate floor.

While Reid did not appear to have pushed for the inclusion in this deal of the "talking filibuster", which would require the opposition to speak continuously on the Senate floor as part of the filibuster process, rather than the current method of merely threatening to do so. However, the Majority Leader did secure a few of the changes sought by many in his caucus, according to Politico:

"Reid (D-Nev.) has been pushing McConnell (R-Ky.) to drop the amount of procedural votes needed to enter a conference with the House, something the two men appear close to agreeing on. Reid has also been demanding that senators stop the practice of extending debate for 30 hours once a Senate filibuster has been defeated. And he’s called for expedited consideration of certain presidential nominations.

In the private talks, McConnell has sought to ensure Republicans get at least two amendments on bills during floor debates, sources say. And Reid appears poised to grant the request, sources say."

As the New York Times reports, these moderate reforms will not satisfy those seeking a more dramatic overhaul, particularly in the wake of impressive electoral victories by President Obama and Senate Democrats:

"The changes will surely disappoint reformers who were pushing for more sweeping revisions to rein in the filibuster, once a rarely used legislative tool. It will not include, for instance, a requirement that senators be present on the Senate floor when they want to block a bill from coming to a vote, continuing the practice of allowing them to filibuster in absentia. And opponents would still have the opportunity to filibuster a final vote on any legislation, thwarting its passage without 60 votes."

The bipartisan Reid-McConnell deal prevents the Majority Leader from resorting to what Republicans call the "nuclear option" and Reid has called the "constitutional option": pushing through changes to the Senate rules with a simple majority, up-down vote, a plan that would need no Republican support. As Neon Tommy reports, this was always the less desirable option, as the precedent would be set for the same mechanism to be used against a potential future Democratic minority.

Read more of Neon Tommy's coverage of filibuster reform here.

Reach Executive Producer Matt Pressberg here.