Two of Obama’s major nominees — Gina McCarthy to head the EPA, and Thomas Perez as secretary of labor — were voted out of committee today in straight party-line votes. Next stop? The Senate floor, where both are likely to be defeated by GOP filibuster.

Look: filibusters of these two nominees are absolutely certain — as has been the case on virtually all of Barack Obama’s nominations. Republicans have made it mandatory for nominations to reach a previously-rare (and almost unprecedented) 60 vote standard.

So the question with McCarthy and Perez is the same as the question is with everything Democrats want in the Senate — can they find five Republicans who are willing to allow a final, simple-majority vote? In other words: can they overcome the Republican filibuster?

There’s still some confusion around the term “filibuster” that needs to be cleared up. Some people are only counting obstruction as a filibuster if a cloture vote — i.e., to end debate — is held. In fact, there is a permanent filibuster underway, in which Democrats know that any arrangement they make with Republicans in which the latter allow permission for a final vote will come with the 60 vote threshold attached as a condition. No 60; no final vote. The cloture vote alone isn’t what makes a filibuster; it’s the insistence on 60 for everything.

And so, again, the big question is whether five Republicans (or more, if one or more Democrats are absent) are willing to support a simple-majority confirmation vote on McCarthy or Perez. If not, the next step will be: what that be enough for Democrats to go ahead with majority-imposed rules change? It remains unclear, but I do think that every case of obstruction brings them a step closer to doing it.

If Mitch McConnell went to the floor of the Senate and announced that Republicans would block literally every single nominee for the duration of the Obama presidency, then Harry Reid would almost certainly change the rules tomorrow. Republicans are not blocking every nominee, but they are blocking far more nominees than was the case for any previous president. The question is, How close are they to crossing the line that will finally force Democrats to take action?