The wait is almost over for what could be the last big legal threat to ObamaCare.

Court watchers are working themselves into a frenzy awaiting a decision on King v. Burwell, one of the most anticipated cases of the year.

On opinion days, dozens of reporters are packing into the court or swarming the steps outside, while nearly 10,000 people tune into SCOTUSblog for live updates. False reports attempting to predict the timing of the decision have only further fueled the hype.

Across Capitol Hill, Republicans in the House and Senate briefed their members for the first time on Wednesday, trying to calm fears about what could happen to the 6.4 million people whose health insurance subsidies are at stake in the case.

Some of K Street’s biggest lobby firms are drafting “predecision” memos and briefing clients, even those outside of the healthcare realm about how they could be hit by a ruling.

Democrats are also getting nervous.

On the same afternoon as the Republican meetings, Health and Human Services Secretary Sylvia Mathews Burwell privately met with members of the New Democrat Coalition on Wednesday to talk about the case.

“In my state of Georgia, 500,000 people would lose their insurance — 8 or 9 million people across the country. And all [states] have to do is put the exchanges in place,” Rep. David Scott (D-Ga.) said as he left the closed-door meeting.

A spokeswoman for the coalition’s chairman, Rep. Ron Kind (D-Wis.), said she couldn’t discuss details, but confirmed the administration’s response to the case was the “main topic of discussion.”

The growing anticipation surrounding King v. Burwell exploded shortly after midnight Wednesday, when news first broke that GOP leaders would begin briefing rank-and-file members about the case.

The meetings took place in separate corners of the Capitol a few hours apart, and both drew unusually large scrums of reporters.

Facing a barrage of questions after the Senate’s lunch-time discussion, Sen. John Barrasso (R-Wyo.) allowed a half-dozen reporters to cram into his elevator, where Sen. Ted Cruz (R-Texas) had already stepped inside.

“Easy, easy,” Cruz said as he was backed into the corner.

“This is an unusual situation isn’t it? We have a presidential candidate in here!” Barrasso exclaimed. He then allowed the gaggle to follow him onto the subway beneath the Capitol Dome and back to his Dirksen Building office, with more questions along the way.

Republicans have spent four months quietly crafting contingency plans for King v. Burwell. While the case drew some attention during oral arguments in March, the hype is approaching new heights with just a few days left of court decisions this summer.

This week’s meetings marked the first time that most members heard details about those plans.

Some members, including Sens. John Cornyn (R-Texas) and Lindsey Graham (R-S.C.), were blunt in their assessment. When asked separately whether the party had reached a consensus about the plan, both flatly replied, “No.” Graham laughed.

Plans in the House appear to be coming along more smoothly. Rep. Paul Ryan (R-Wis.), the GOP’s point man for the case, presented a more complete proposal that would give block grants to states that want them. The rest could decide to scrap the healthcare law altogether.

But even that plan sparked fireworks from the House’s more conservative members. Rep. Paul Gosar (R-Ariz.) rolled out a bill the next day that would prevent Congress from enacting any extension of the subsidies.

The spotlight stayed on King v. Burwell on Thursday, as the Supreme Court release its latest round of opinions.

The day before, CNBC reporter Larry Kudlow tweeted that the case would be released on Thursday, citing “people in the know,” causing a firestorm of speculation.

Despite his “red alert,” none of the five cases that day involved ObamaCare.

With just a few days of opinions left, the Obama administration is also beginning to break its silence.

Burwell and other health officials have been so adamant about refusing to discuss case that senior Republicans like Cornyn have accused of Burwell acting in contempt of Congress.

While Burwell’s department has given no official guidance to the three dozen states that could lose their subsidies, the administration is starting to show its hand.

This week, the Department of Health and Human Services (HHS) gave permission for two states to move ahead with backup plans to save their subsidies, which would involve launching their own health insurance marketplaces.

A few states, like Florida, Louisiana and Wisconsin, have said they will do nothing to rescue ObamaCare subsidies.  

But the vast majority of state leaders are staying quiet about their post-decision strategies, which have been shaped by secret meetings and phone calls with other states over the last few months.

Those concerns are being relayed to the 68 senators and hundreds of representatives whose constituents are at risk of losing their subsidies.

“I just got off the phone with one of our state legislators, trying to get some direction here on how it’s going to be enacted,” said Sen. Ron Johnson (R-Wis.), who has put forward his own bill to address the King v. Burwell fallout.

“We have to wait for the Supreme Court decision. I mean, this may all be moot. I hope not, I hope the Supreme Court rules as the law was actually written,” he said.

In conversations about the case, it’s clear some lawmakers are getting jumpy.

Rep. Phil Roe (R-Tenn.), who leads the House GOP Doctors Caucus, volunteered a dire prediction for his side: “I think it’s going to be 5-4 in favor of the government.”

Peter Sullivan and Mike Lillis contributed.