They came. They saw. They protested.

Yet it remains to be seen whether the demonstration Saturday in the nation's capital, against what protesters view as out-of-control spending by an expanding federal government, will conquer Washington.

The tens of thousands of protesters marched to the U.S. Capitol chanting various slogans and waving posters that voiced a rather broad array of grievances against big government and the leaders, particularly President Obama, who the protesters blame for its size and scope.

Some signs, reflecting the growing intensity of the health care debate, depicted President Obama with the signature mustache of Nazi dictator Adolf Hitler. Many made reference to Obama as a socialist or communist, and another imposed his face on that of the villainous Joker from "Batman." Other protesters waved U.S. flags and held signs espousing fiscal conservatism, declaring "I'm Not Your ATM" and "Go Green Recycle Congress."

The rally, and others like it, have been billed as "tea parties," part of a movement that takes its cue from the Boston Tea Party and other imagery from the days of the founding fathers. On Saturday, men wore colonial costumes as they listened to speakers who warned of "judgment day" -- Election Day 2010.

FreedomWorks Foundation, a conservative organization led by former House Majority Leader Dick Armey, has organized several groups from across the country for the Saturday event, dubbed a "March on Washington."

Demonstrators chanted "enough, enough" and "We the People." Others yelled "You lie, you lie!" and "Pelosi has to go," referring to House Speaker Nancy Pelosi, D-Calif. Some carried signs with slogans such as "Obamacare makes me sick"

The line of protesters clogged several blocks near the capitol, according to the D.C. Homeland Security and Emergency Management Agency. 

The demonstration was part of the so-called Tea Party Movement that gathered steam in April to protest tax policies. And Saturday's event was the culmination of a 34-city, 7,000-mile bus tour that began Aug. 28 in Sacramento, Calif. 

The "partiers" have cited a host of grievances and demands, such as a call for any health care reform to create more competition and be guided by market principles, not a government-run plan.

Organizers said they anticipated tens of thousands of proponents of limited government to attend. They said it would be the largest group of fiscal conservatives to ever gather in Washington.

Lawmakers also supported the rally. Rep. Mike Pence, chairman of the House Republican Conference, said Americans want health care reform but they don't want a government takeover.

"Republicans, Democrats and independents are stepping up and demanding we put our fiscal house in order," Pence, of Indiana, told The Associated Press.

"I think the overriding message after years of borrowing, spending and bailouts is enough is enough."

Rep. Tom Price, R-Ga., and Sen. Jim DeMint, R-S.C., also spoke at the rally. DeMint said he'd had enough of "Alice in Wonderland" politicians promising more programs at the risk of financial disaster.

"The president has warned us if we disagree with him he's going to call us out," DeMint said. "Well, Mr. President, we are out."

Richard Brigle, 57, a Vietnam War veteran and former Teamster, came from Paw Paw, Mich. He said health care needs to be reformed -- but not according to President Barack Obama's plan.

"My grandkids are going to be paying for this. It's going to cost too much money that we don't have," he said while marching, bracing himself with a wooden cane as he walked.

The rally comes on the heels of heated town halls held during the congressional August recess when some Democratic lawmakers were confronted, disrupted and shouted down by angry protestors who oppose President Obama's plan to overhaul the health care system.

"I can't figure out to save me what [Mr. Obama and the Democrats] are trying to accomplish, unless they want socialism,"  73-year-old Joseph Wright, a retired paper-mill worker, told The Wall Street Journal. 

Wright rode from Tallahassee, Fla., to Washington this week on one of the many chartered buses bringing in demonstrators from states as far-flung as Massachusetts and Arkansas.

Many protesters said they paid their own way to the event -- an ethic they believe should be applied to the government. They say unchecked spending on things like a government-run health insurance option could increase inflation and lead to economic ruin.

Terri Hall, 45, of Starke, Fla., said she felt compelled to become political for the first time this year because she was upset by government spending.

"Our government has lost sight of the powers they were granted," she said. She added that the deficit spending was out of control, and said she thought it was putting the country at risk.

Other sponsors of the rally include the Heartland Institute, Americans for Tax Reform and the Ayn Rand Center for Individuals Rights.

Norman Kennedy, 64, of Charleston, S.C., said he wants to send a message to federal lawmakers that America is "deeply in debt." He said though he'd like everyone to have free health care, he said there's no money to pay for it.

"We want change and we're going to get change," Kennedy said. "I want to see fiscal responsibility and if that means changing Congress that will be a means to that end."

The White House on Friday claimed it was unaware of the planned rally.

"I don't know who the group is," White House spokesman Robert Gibbs told reporters with a shrug.

But a House leadership aide warned fellow Democrats that up to 2 million demonstrators could turn out.

"It looks like Saturday's event is going to be a huge gathering, estimates ranging from hundreds of thousands to 2 million people," Doug Thornell, an aide to Rep. Chris Van Hollen, D-Md., wrote in a memo obtained by FOXNews.com.

But conservatives believe the memo is ploy to inflate expectations for the turnout anticipating that it will fall short.

"It's an old political tactic to get out in front and make wild projections and when they're not met, claim their opponents don't have the juice," said Pete Sepp, a spokesman for the National Taxpayers Union, one of the organizers of the rally.

The Associated Press contributed to this report.