WASHINGTON: The US Supreme Court on Monday threw out a suit alleging that President-elect Barack Obama is not a natural born American and therefore ineligible for the presidency. As for the inauguration, planners say the Inauguration celebration will be both an 'opportunity' and 'nightmare' for D.C.

The court did not give a reason for rejecting the case, which was the second such challenge the justices have refused to take up in recent weeks.

Without comment, the court brushed off the lawsuit claiming Obama didn't meet the Constitution's citizenship requirements. The move undercuts but doesn't end a legal campaign that's gotten far more traction on the Internet than in the courts.

Justices must still dispose of at least one other legal challenge to Obama's eligibility. Promoted on websites and in the conservative media, the various challenges differ somewhat in detail but build on common questions and insinuations about the circumstances of Obama's birth.

"Since candidate Obama was born to a Kenyan father, he is not eligible to the office of the President since he is not a natural born citizen," said retired attorney Leo C. Donofrio in his petition to the Supreme Court.

Obama was born in Hawaii. His mother was a US citizen and his father, a native of Kenya, was a British subject.

The same, now defunct suit by Donofrio of New Jersey also charged that John McCain is not a native-born American either so couldn't become president.

McCain's father, a career Naval officer, was stationed in the Panama Canal Zone when McCain was born in 1936 in a US Navy hospital on a US military base in a then-US territory, which was controlled by the United States until 1979.

In an earlier case, which the court threw out on the eve of the historic election in which Obama beat McCain to become the first African-American to be elected president of the United States, Pennsylvania lawyer Philip Berg alleged that Obama was born in Kenya, his father's homeland.

While the Obama team has largely dismissed questions about his citizenship, the persistence of the questions drove the campaign in June to make public his birth certificate. It shows, among other things, that he was born in a Honolulu hospital at 7:42 p.m. on Aug. 4, 1961.

Anyone born on US soil is a US citizen, regardless of his or her parents' immigration status. Hawaii has been a state since 1959.

The internet furor over Obama's birth during the election led his campaign team to release his birth certificate online, but this did not silence the critics who believed it to be a fake. However, the certificate inspected by Factcheck.org shows that Obama was born in Hawaii two years after it became a US state. Obama's birthplace was also confirmed by the director of Hawaii's Department of Health on Oct. 31.

"Of course, it's distantly possible that Obama's grandparents may have planted the announcements just in case their grandson needed to prove his US citizenship in order to run for present someday," FactCheck.org noted. "We suggest that those who choose to go down that path should first equip themselves with a high-quality tinfoil hat."

Another such group, PolitiFact.com, concluded: "It is possible that Obama conspired his way to the precipice of the world's biggest job, involving a vast network of people and government agencies over decades of lies. Anything's possible. But step back and look at the overwhelming evidence to the contrary and your sense of what's reasonable has to take over."

So, this means that Obama's January inauguration is still good to go.

This brings us to a real problem - how to deal with the hordes of people expected to attend Obama's inauguration celebrations, which is expected to create both an economic boom and a logistical nightmare for the District.

With as many as 4 million people may visit the region that week - about one-fifth the number that typically visit the region in one year - "is an enormous opportunity or logistical nightmare" said Jim Dinegar, president of the Board of Trade.

Dinegar said there were requests for parking spaces for 10,000 buses, enough to stretch around the Capital Beltway and up to Baltimore.

Companies should plan for emergencies, delays in delivery of goods due to packed roads, communications failures and other infrastructure deficiencies, according to Charles Fishher, vice president of James Lee Witt Associates. "When you bring this many people into the area you are going to see some stress to the system," he said.

Hotels, caterers and restaurants have been planning for months, ordering as much as they can beforehand and hiring extra staff, according to Bill Hanbury, president and chief executive of Destination D.C., but he encouraged them to add decorations, signs and welcoming materials for visitors.

The Presidential Inauguration Committee is expected to announce 10 official balls that Obama will attend, Hanbury said, and 45 other non-official balls have already been planned.