Updated at 4:25 p.m.

Crowds are dispersing after a rousing speech by President Obama. Interrupted frequently by applause, a relaxed Obama told listeners that health care reform was part of a “promise” he made during the presidential campaign to be responsive to the needs and aspirations of the middle class.

During the speech, Obama thanked Maine Reps. Chellie Pingree and Mike Michaud, and referred to the “many hours” he spent discussing the bill with Republican Sen. Olympia Snowe.

In response to someone yelling out “Thank you!” in the crowd, Obama responded: “Thank Chellie and Mike, they voted for it.”

Obama described the legislation as “common sense” and said he “welcomed” efforts to repeal it.

“What this fight has taught us – about ourselves and about this country – it’s bigger than any one issue,” Obama said.

“It has reminded us that we, as a people, do not shrink from a challenge. We overcome it. We don’t shrink from a challenge, we don’t shirk our responsibility. We embrace it. We do not fear the future. We shape the future. That is what we do. That is who we are. That’s what makes us the United States of America.”

3:34 p.m.

About a thousand or more people were still waiting outside the Expo at 3:20 p.m. when word started to trickle down the line that the president was already inside the building beginning his remarks.

Josh Delano, 24, who lives about a block away, spent three hours in line today and another 2 1/2 on Wednesday getting tickets. He quickly left with a friend to try and catch Obama’s speech on TV.

“I guess I assumed that if you had tickets you’d get in. Frustrated is the best word to describe it.”

Cliff Rossignol, 75, and his wife Mariette, of Scarborough, were among the hundreds of ticketholders who were turned away.

“It’s very disappointing. If they would have notified us we could at least have gotten to a TV set.”

2:58 p.m.

A Coast Guard helicopter made three sweeps overhead just after 2:30 p.m. as a massive line of people holding tickets still stretched from the Expo and all the way over I-295 on Deering Avenue.

Some started to get concerned that they would not gain entrance before the Expo building is expected to be sealed at around 3 p.m.

Among those concerned was Freeport High School senior Kaylon Brown.

“Did they overbook it?” she said. “They made it clear you needed a ticket and they said be here early.” Brown and her friends started moving forward with anticipation.

2:50 p.m.

Denise Shames of Portland waited in line Wednesday for a few hours and got in line again today at 9, hoping to be near the stage. Now, she Dian Westfall of Cape Elizabeth are standing in the crowd at the Expo, about half of a basketball court away from President Obama’s lectern.

“I’m less than five feet tall. I won’t see anything,” Shames said, laughing. Is she disappointed? Not at all.

“It’s fabulous to be here.”

2:28 p.m.

Members of the Maine Red Claws arrived around 2 p.m. and slipped into the procession at the Portland Expo, awaiting their chance to see the president speak.

As the line moved, the sound of anti-Obama protesters’ ringing handbells and the pro-Obama chants of “Yes we can” grew louder and louder.

1:50 p.m.

Media representatives are now being screened and allowed into the Expo.

Cameras, computers and bags were laid out on the sidewalk and sniffed by a German shepherd before security workers used metal detector wands to screen the journalists.

Audience members also are flowing into the front of the hall, standing on the floor near the stage, or sitting along the side to the left. The Fort Fairfield basketball team, a special guest of U.S. Rep. Mike Michaud, is standing near the stage in their state championship jackets.

1:30 p.m.

Most of the thousands who had gathered at the Portland Expo by early afternoon clutched tickets to go inside.

But not everyone. Conservatives Beth and Jack Wadsworth of Hiram, who manage timberland for small landowners, did not have tickets.

They said they had never been moved to protest during any previous administration. Beth Wadsworth held a sign that read: “Obama’s chapter in history: Chapter 11.”

Jack Wadsworth, who currently provides health care for five employees, worries how his bottom line will be affected by the new health reform legislation.

“It’s already very expensive, and right now we don’t know how it’s going to affect us,”

Said his wife Beth: “We can’t keep printing money.”

12:59 p.m.

Scores of protesters and supporters have assembled with signs on a part of Park Avenue that has been barricaded off in front of the Expo in anticipation of the presidents arrival.

Protesters held signs with messages like, “Marxist in Chief.” One recently graduated college student had a lighthearted approach. The sign held by Jameson Frederic, 23, of Cumberland read “Hey, Prez, beer summit in the Old Port after speech?”

Frederic said “We can all get along. Liberals and Conservatives can agree. Beer is great.”

On a more serious note, Frederic would like to hear the president speak about the war on obesity in America where he believes the root of many healthcare problems stem.

Congressman Mike Michaud arrived around 12:30 and right behind him were 14 members of the Fort Fairfield Class D girls championship basketball team. Michaud got the group ticket because he was proud of their achievements. One of the players, Kelsie Wilson, said “I heard him over there bragging about us. This is just another team bonding experience for us.”

Updated at 12:10 p.m.

By noon the line of people waiting to get into the Portland Expo turned the corner off Park Avenue and stretched down Deering Avenue by King Middle School.

Ryan Willette, a small business owner from Winslow, pulled her 9-year-old son Arnold Maroney from a class field trip to witness today’s  speech by President Barack Obama.

Willette owns Bee’s Snack Bar in Winslow. She said she believes in health care reform even though the details are still unclear.

“I think it’s going to help everyone in the long run,” she said. “It will be worth it for everyone as a whole.”

As lunch hour arrived, people ate sandwiches they had brought from home or purchased from local stores.

11:25 a.m.

Frank and Pat Giordano, 63 and 62, of Newport were the first vocal protesters to arrive on the scene at the Portland Expo, around 11 a.m. today.

The pair held a sign reading “Obama lied when he took the oath of office to uphold our Constitution of the United States and its people,” and a second sign reading “Obama and Congress are traitors to our Constitution.”

The Giordanos did a television interview just after 11 a.m. as Obama supporters gathered behind them to yell “Yes We Can.” The pair said they are meeting a group called the Maine Patriots at 12:30.

“The health care, they’re forcing it down our throats,” Frank Giordano said. “They’re not listening to the whole country.”

Giordano is a former small business owner who said he dropped his health insurance because it was too expensive.

“I’m still not happy they pushed it through,” he said.

10:45 a.m.

The sun came out around 10:30 a.m. as cars honked along Park Avenue in repoonse to signs being handed out that read “Yes We Can” and “Standing Together for Health.”

University of Southern Maine students Will Douglas, 24, and Daniel Crothers, 25, had been in line since 7 a.m., and were about 40 people deep from the front. Both students had laptops and sat on the sidewalk doing school work.

Crothers, who is originally from Kingston, Ontario, was skipping a physics class, a physics lab and a biology lab, but believed making time for today was important.

“I follow politics quite closely. I don’t expect to hear anything new today, but why I’m really here is to have a shared experience. I’m really excited to see a U.S. president.”

Crothers is one of several in line who does not have health insurance.

“Up until this big step,” he said, referring to the recent passage of national health care reform, “I figured I’d drive home to Canada if I got sick.”

10 a.m.

By 9:30 a.m. a crowd of about 100 people gathered behind green barricades on Park Ave. Thursday morning awaiting the arrival of President Obama. Some, sitting in camp chairs or on the ground, arrived as early as 5 a.m.

Satellite trucks from area news stations were lined up in the adjacent parking lot as local and national media dropped off equipment at the Expo in preparation for the president’s 3:25 p.m. speech.

John Faunley left Madrid at 2:30 a.m. arriving before the sun rose.

“In my opinion the press is focusing too much on the shrill of the right. It’s so fear based, unreal, and mean spirited,” said Faunley. “I decided to actually do something and come here to support this President.”

Faunley had been chatting since the early morning hours with new friends Judie Giusti of Portland and Tom Bolduc of Lewiston.

“I’m here to give my whole-hearted, 150 percent support to our President Barack Obama. He needs all of us to support him,” said Giusti who is first in line.

Bolduc was inspired to make the trip down after hearing Obama speak about the historic health care reform bill.

“I was very impressed and moved. He’s  He’s working for the people. That’s a radical change and it’s moving me,” said Bolduc. “He’s a man of dignity. He’s a man of honor.”

Staff Writer John Richardson contributed to this report.