Washington - The White House was quiet, a solitary secret service agent visible on the roof. Then, just after midnight Wednesday, a chant of "Yes we did! Yes we did!" echoed outside 1600 Pennsylvania Avenue.

At least 1,000 exultant supporters of president-elect Barack Obama collected quickly and chanted in unison. Many sang, waved flags, hoisted banners and held up flaming lighters. Some celebrated quietly in small groups. A few wept and hugged friends and family.

One woman even held up her little white poodle in the pouring rain and commanded: "Bark, bark at Bush."

That immediately inspired a more belligerent group to taunt the unpopular president: "Bush, Bush, come out now. Bush, Bush, get out now."

As scores of flash bulbs popped in front of the presidential residence, African-American Chantelle Williams, 29, said: "My mama told me to vote, and I did. The White House now belongs to me, to all of us. ... Change was coming - now it's come."

A handful of police officers, looking somewhat inadequate, could only stare as people ignored them and kept streaming into the pedestrian zone outside the White House. Even when people left the area, twice as many seemed to squeeze their way in. On the streets, a block away on either side, drivers in cars and trucks honked and shouted from their open windows: "Obama! Obama!"

"It is an unbelievable moment in time - it only comes around once in a generation," said salesman George Page, 53. "This is magical. This is not a movie, it's not TV. This is live and real. Obama will change the path of America."

Yvonne Green, a 30-year-old doctoral student who returned to Washington this year, said: "I'm a US citizen but have been in London for the last four years. I was so sick and tired of being a de facto US ambassador in my travels around the world - explaining to foreigners that not everyone likes Bush, or is like Bush.

"If Obama had lost, I would have packed my bags and left. The last four years has almost been like a loss of a home and identity for me - it was terribly isolating."

It wasn't just US voters who were celebrating Obama's victory. Marcelo Daniel Vaquero, 28, said he came to Washington from Buenos Aires to be a witness to the ground-breaking election.

"It's a dream come true. As a foreigner, even I'm so moved by what happened tonight. I can imagine how Americans feel," Vaquero said, before rushing off to be photographed with his three friends in front of the White House. "We love Obama in Latin America."