An opposition rally, news conferences, squads of talk radio hosts, doctors in scrubs and Republican opponents by the busload will all be part of the furor surrounding proceedings on the Patient Protection and Affordable Care Act.

The high-stakes hearings from Monday to Wednesday are the perfect stage for the law's opponents and supporters to put their cases before the U.S. public, lawmakers and media, organizers said.

"It's an opportunity to take advantage of the media interest in this and try to explain how the Affordable Care Act will function," said Ron Pollack, executive director of Families USA, one of the main groups supporting the two-year-old law.

The National Federation of Small Business and 26 states are challenging the law, whose key feature requires most adults to buy health insurance. The court is not expected to rule until as late as June 30.

Families USA and other organizations, including the Service Employees International Union and Health Care for America Now, are setting up media in a building across the street from the Supreme Court's main entrance.

The building will house 27 talk-show radio hosts who will broadcast live during the six hours of hearings, the longest time allotted to a single topic by the court in 44 years.

News conferences by supporters of the law are planned before the start of each day's hearings. Monday's will feature doctors and nurses in surgical scrubs and people with stories about healthcare.

A prayer vigil and daily post-argument briefings will also be on tap, Pollack said.

"We think this is a teaching opportunity," he said.

CAPITOL HILL RALLY

Levi Russell, a spokesman for Americans For Prosperity, a group that opposes the healthcare law, said the main event by opponents would be a Capitol Hill rally on Tuesday that would bring together about two dozen groups.

Americans For Prosperity itself is bringing in at least 3,000 supporters on 50 to 60 buses for the event, which will feature addresses by U.S. Representatives Michele Bachmann and Paul Ryan, he said.

"Our purpose is to send a message to Capitol Hill at large that our activists are still very opposed to this legislation," he said.

Simultaneous rallies against the law are planned in Missouri, Ohio, Maine, Colorado and Montana. Americans For Prosperity will deliver a statement to the court signed by a 50,000 people.

The conservative Tea Party movement, which backs smaller government, has also scheduled a rally on Capitol Hill for Saturday, Russell said.

In a sign of the media furor, court spokeswoman Kathy Arberg said 117 reporters had been issued courtroom credentials. Another 15 will get space in court offices.

The normal number of reporters at a hearing is about 25, she said. Public seating has been expanded to 60 from 50.

Five people were already in line for seats outside the columned court building on Friday afternoon. Most were holding places for other people under an unseasonably hot March sun.

Andrew Winter, 24, of Philadelphia, was holding the third spot for a friend, and said the hearing was important because "it's one of the first cases in a very long time that has to do with every single American."

Pollack, of Families USA, said 60 to 80 groups supporting the law had met two weeks ago to discuss coordinating efforts during the hearings.

White House representatives were at the meeting but had no coordinating or organizing role, he said.

(Reporting By Ian Simpson; Editing by Paul Thomasch and Cynthia Johnston)

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