Is Congress really going to allow the President to escalate military action against ISIS without voting on it? There almost certainly won’t be any vote before the midterm elections. But there is still another way: Members of Congress could try to force a vote on authorization of force after the elections — during the lame duck session.

A couple times in the past few years, a left-right coalition of antiwar progressives and libertarian conservatives has come together to try to check presidential power in the realm of national security, and to act as a counterweight to the many “hawks” in Congress. Last summer such a coalition came remarkably close to passing an amendment that would have defunded NSA bulk surveillance. Then, a few months later, a very similar coalition rose up against Obama’s proposed military action in response to Syria’s use of chemical weapons, which ultimately was shelved in the fall of 2013.

Where is that alliance right now? Dem Rep. Adam Schiff of California, who is playing a key role in trying to organize in Congress in support of a vote on action against ISIS, notes that conservative libertarians in the House have been comparatively silent this time around, and asks why.

“It’s hard to explain the relative silence of my libertarian colleagues at a time when the president is about to announce a war effort that may take years,” Schiff tells me. “There have been only a couple of libertarian voices in Congress, mostly in the Senate, raising the issue of Congress’ role in declaring war and authorizing the use of military force.”

Senator Rand Paul — perhaps the highest-profile libertarian Republican in Congress — has raised concerns about the need for such a vote, but many other members of Congress, leaders in both parties included, seem content to let the President act without one. Congressional liberals are split on whether they support escalated military action itself, but they largely agree that there should at least be a vote on it. However, the Rachel Maddow Show’s whip count of people calling for a vote on escalated military action against ISIS contains the names of very few Republicans.

Whatever the reason for this — it could be that Republicans are reverting to traditional hawkishness, or that they don’t want this vote before a midterm election they think they are poised to win — this left-right alliance may be faltering this time around. Still, Rep. Schiff tells me there is cause to believe there still could ultimately be a genuine push in Congress for such a vote.

“While we don’t yet see a coalition strongly in support of the Congressional prerogative to declare war, it could still materialize,” Schiff says. “I could see a coalition between the libertarian right and progressive left, and Constitutionalists in the middle, all coming together to say we need a vote.”

And just because it is unlikely to happen before the election doesn’t mean it won’t happen at all, Schiff adds: “It’s more likely to happen in the lame duck session. But I don’t see why we can’t put that language together right now.” In other words, a vote after the elections might still be worth pushing for.

By the way, more than seven in 10 Americans think Congress should vote on whether to authorize military force against ISIS. Not that this will necessarily have any impact on what Congress does in the end, but it seemed worth mentioning.