WASHINGTON -- Tea Party and union members, liberals and conservatives, Republicans and Democrats have two things in common as the Supreme Court prepares to announce its verdict on President Obama's health care law Thursday.
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They have no clue what the court will decide. And they will have plenty to say outside the court immediately after - in high praise or denunciation.
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Much like the court's three days of oral arguments on the Affordable Care Act in late March, Thursday will feature a crowded, hushed courtroom and a cacophonous series of sidewalk demonstrations.
For some lawyers and lawmakers who have fought the health care battle for years - and in some cases, decades - it's an opportunity to witness history inside the marble courthouse.
"There's an atmosphere of intense, quiet excitement," says Neal Katyal, who represented the Obama administration before the court as acting solicitor general in 2010-11. "People are sitting in that room knowing history is about to be made."
Ron Pollack, executive director of the health consumer group Families USA, has been there the past three days the court delivered opinions, just in case health care was among them. Thursday, he plans to arrive several hours early to make sure he picks up every nuance from the nine justices.
Pollack's allies will be outside as well, to react before dozens of TV cameras. Within minutes, the group plans to send its analysis and recommendations for further action to more than 100,000 supporters. It has prepared eight news releases based on potential court rulings.
"It's going to be packed," Pollack predicts. "We're going to have a lot of people outside. They will have signs, and they will chant dignified but positive things about the legislation."
On the other side of the debate, Tea Party demonstrators also will be out in force. They plan a "flash rally" in front of the court, thanks to "Minutemen" coming from hours away.
Within 36 hours, the Tea Party Patriots plan a teleconference for their members with key opponents of the law, including Sen. Rand Paul, R-Ky., and Rep. Michele Bachmann, R-Minn.
Members of Congress will be inside and outside. House Speaker John Boehner, R-Ohio, will dispatch two members of his leadership team, Reps. Cathy McMorris Rodgers of Washington and Tom Price of Georgia. Boehner has vowed to seek repeal of any portions of the law left standing by the court.
Liberal Democrats, anticipating that the court's conservative majority may strike at least part of the law, plan to march from the Capitol to the court with signs urging "Medicare for all," a type of government-run health care. Among them will be Reps. Raul Grijalva of Arizona and Keith Ellison of Minnesota.
Some of the most prominent advocates involved with the case won't attend - they'll be busy reading and responding.
Randy Barnett, a Georgetown University law professor and plaintiff in the case on behalf of the National Federation of Independent Business, will be reading the justices' opinions, writing on legal blog sites, doing radio commentary and fielding a steady stream of media calls.
"This has turned out to be the biggest case in our lifetime," Barnett says. "This is really a case that's up there at the level of Brown v. Board of Education," the 1954 desegregation case.