WASHINGTON — Tens of thousands [ 2 million ] of people from across the country arrived here Saturday to demonstrate against what they say is an ever-expanding intrusion of government in their lives in a culmination of a summer-long season of protests that began with an opposition to health care and grew into a broader dissatisfaction with Washington.

Protesters in Washington D.C. during a rally on Saturda

A sea of people stretched along Pennsylvania Avenue from the Capitol to the White House on a cloudy and cool day, with scores of hand-written signs telling of their frustration. They sang verse after verse of patriotic songs like “God Bless America,” even as others shouted angry criticisms of President Obama and Congress.

“I want Congress to be afraid,” said Keldon Clapp, 45, an unemployed marketing representative who recently moved to Tennessee from Connecticut after losing his job. “Like everyone else here, I want them to know that we’re watching what they’re doing. And they do work for us.”

As Mr. Obama traveled to Minnesota on Saturday to rally support for his health care plan, he flew over the crowd in Marine One. The helicopter could be seen flying overhead as the demonstrators made their way toward Capitol Hill from downtown Washington.

The police declined to provide a precise crowd estimate, but the demonstrators filled the west lawn of the Capitol and stretched for block after block and onto a portion of the National Mall. The authorities urged protest organizers to begin marching 20 minutes early, because the crowd was too large to fit in Freedom Plaza near the White House.

“This is not some kind of radical right-wing group,” Senator Jim DeMint, Republican of South Carolina, said in an interview as dozens of people streamed by him. “I just hope the Congress, the Senate and the president recognize that people are afraid of what’s going on.”

Mr. DeMint and a handful of Republican members of Congress were the only party leaders on hand for the demonstration. Republican officials were pleased by the crowd turnout, but also wary of the anger directed at incumbents of all stripes.

They came by bus, car and airplane, arriving here from Texas and Tennessee, New Mexico and New Hampshire, Ohio and Pennsylvania. The messages on their signs told of an intense distrust of the government, which began well before Mr. Obama took office and extends far beyond the effort to overhaul health care. One sign declared: “We are under attack by our own government.” And several signs said, “Our Constitution has termites!”

The protest, organized by anti-tax groups, opened peacefully, with few visible signs of counter-protesters.

While there was no shortage of vitriol among protesters, there was also an air of festivity. A band of Revolutionary War protesters in colonial gear wound through the crowd, led by a bell-ringer in a tri-corner hat calling for revolution. A folk singer belting out a protest ballad on a guitar brought cheers from listeners.

Paula Davis, 55, and her husband, James Davis Jr., a retired United States Air Force lieutenant, stood by the band and handed out small American flags to passers by. The two had flown to Washington from Corrales, N.M., and a huge yellow state flag snapped in the breeze overhead.

Ms. Davis said that no single issue prompted her to come to the capital, saying: “It’s everything.” She listed health care and energy legislation among them. Mr. Davis added, “It seems like everything that this administration seems to be doing is promoting job loss and making the situation worse.”

Throughout the morning, more and more demonstrators arrived, identifying themselves as Republicans, libertarians and independents. Several speakers denounced the Obama administration’s health care plan as “socialism.” A few Confederate flags waved in the air, but there were hundreds of American flags and chants of, “USA! USA! USA!” A young girl held a sign, saying: “Don’t redistribute the wealth of my Barbies.”

Ruth Lobbs, 57, a school teacher from Jacksonville, Fla., said she flew to Washington on Saturday to protest how she believes the government has violated the Constitution. She said she did not vote for the president, adding that her anger has been building for years.

“It’s more than Obama. This isn’t a Republican or a Democratic issue,” Ms. Lobbs said, as she held a yellow flag that declared, “Don’t Tread on Me.”

“I don’t know if anything will come of this or not,” she said, “but this is a peaceful way of showing our frustration.”

Mike Bileca, a Republican from Miami, and his wife, brought their three young children. Mr. Bileca said he was fed up with Republicans and Democrats alike, for what he believed was excessive spending practices and unresponsiveness to constituents.

“We want to make sure that this country is preserved for them,” he said of his sons. “If someone doesn’t stand up, then they’re going to have nothing.”

Theo Emery and Ashley Southall contributed reporting.

www.nytimes.com/2009/09/13/us/politics/13protestweb.html