Facing Republican filibuster threats over a handful of President Obama's high-level nominees, Democrats are threatening to invoke the so-called nuclear option and revise the Senate's rules to effectively circumvent such obstruction.

Sound familiar?

Senate Majority Leader Harry Reid (D-Nev.) has floated similar threats before. Yet this time, with top cabinet picks on the line, there's reason to believe he's finally ready to pull the trigger.

"It hasn't gotten too much attention given the other things that are going on, but there is a battle looming this summer over the filibuster, one that could be a significant milestone in the already poisonous relationship between the parties on Capitol Hill," says The American Prospect's Paul Waldman.

On Wednesday, Reid pulled a scheduled vote on Richard Cordray, Obama's pick to lead the Consumer Financial Protection Bureau, moving it instead to July. Reid is now planning to cluster that vote with votes on Gina McCarthy, the president's pick for EPA chief, and Thomas Perez, his Labor Secretary nominee.

Moving the vote allows Democrats to focus all their efforts on a pending immigration bill, but it also serves a second purpose. Democratic aides reportedly feel that Republicans would either have to abandon their filibusters, or, by stonewalling a string of nominees, give Democrats the political cover necessary to "go nuclear" and revise the Senate's rules to prevent filibusters on executive and judicial branch nominees.

Here's Talking Points Memo's Brian Beutler on that tactic:

That effectively puts Reid and Minority Leader Mitch McConnell on a collision course. If McConnell caves or works out an agreement with Reid, then the nuclear option will become inoperative. But if he doesn't and these confirmation votes fail, then Reid will either have to admit defeat or do…something. In that sense he's essentially building a "permission structure" for himself and his caucus to do something about the rules in the event that Republicans make good on their threats. [Talking Points Memo]

After moving the nomination vote, Reid hinted that he was, in fact, gearing up for a filibuster showdown over those votes:

According to the Washington Post's Greg Sargent, Reid has already secured the president's approval for going that route should the GOP block the three nominees. As he notes, the goal is not to end the filibuster entirely, but only to remove the 60-vote threshold on key presidential nominations.

Still, he cautioned Democrats to view this as a last resort.

"The key dynamic is that Democrats — Reid included — don't really want to exercise the nuclear option, and would far prefer it if Republicans stand down, even to some degree, in their filibustering of nominations," he says. "Republicans will continue to test just how much they can get away with. But there is plainly a line that they can cross that will trigger action on Reid's part."