OTTAWA - A flash of smile and a wave through a window were enough to electrify Barack Obama fans as they lined slush-covered streets to watch the U.S. president's motorcade speed by.

That fleeting brush with high-voltage charisma Thursday left schoolgirls screaming and moved strangers to hug each other.

"He waved at us!" four teenaged girls squealed in unison after the president's armoured limousine turned a corner near Parliament Hill under the watch of a hovering police chopper.

The teens said their parents allowed them the day off school to witness the first African-American U.S. commander-in-chief making his first foreign visit. They were among hundreds of supporters - many waited for more than two hours - who stood bundled against a damp cold that was just over freezing.

"We love Obama!"

Even game-faced police officers got caught up in the rare moment, including one who posed for a snapshot after the line of bullet-proof black vehicles had passed.

"My son will like a photo," he said.

It was an unforgettable day for Carrie Kristal of Ottawa. She and her husband Henry took their baby niece, Ines, to a corner along the Rideau Canal where they hoped Obama's motorcade would pass. They waited with about 50 other people as the flashing lights and 50-car parade approached.

For a split-second they had a clear view of Obama himself, Kristal said.

"You could very distinctly tell it was the president. He was on our side and he waved at our group. There was just such delight. People who didn't know each other were hugging each other."

Kristal began watching Obama's campaign more than a year ago as it first began to build steam.

"His whole campaign for election was on hope. We see so much here of politicians who want to divide and conquer. There's so much cynicism. And this man was all about hope. He inspired the whole world.

"I'll be telling my one-year-old niece that she got to wave at the president and he waved back. She's a good waver."

The crowd vibe along the motorcade route was one of excitement and easy rapport as strangers swapped stories of why and how far they came.

Marie Schofield and her friend Dagmar Weinert caught a bus at 4 a.m. for the five-hour trip from Kitchener, Ont.

"I think this is special," Schofield said. "It's unique, it's once in a lifetime."

Colin Schultz, 22, who's studying physical science and philosophy at University of Guelph, thinks Canada could use a shot of Obama-style politics.

"It's different from what we've got here. I think if a character with that sort of charisma came into the light in Canadian politics, people would just eat it up. They would just love it.

"You can see it in the way he ran his campaign. He brings a different approach - more about getting people involved, getting people involved to help out themselves. ...

"You can see that he's a different kind of person," Schultz said. "He seems a lot more honest."

The Obama Effect on those who waited outside Centre Block for the president to wrap up his four-hour visit with Prime Minister Stephen Harper was nothing short of extraordinary.

As Obama's limousine made its way along the circle drive away from Parliament, people ran across the snow-covered lawn trying to get a better look.

They yelled and waved as the long line of cars pulled away from the crowd and down the street. Obama made a surprise stop in the Byward Market to pick up some gifts and a specialty Obama BeaverTail - a fried-dough delicacy topped with cinnamon, sugar and a big chocolate O.

Adman Ustun was going to try to say hello when the president suddenly came right into his store, Oxxo Silk and Gift.

Obama bought a key chain with a moose on it for one of his two daughters. She collects them, Ustun said.

"He asked me how much and I said $4 and he gave me a $5 bill - Canadian. It was very exciting."

Wowed onlookers stopped, stared and fumbled for their cameras.

You don't see that every day in Ottawa.