As the "Occupy Wall Street" demonstration enters its fourth week this weekend, Police Commissioner Ray Kelly says he estimates the protests have already cost the department $1.9 million in overtime.

The demonstration is mostly centered in Manhattan's Zuccotti Park.

Ballooning crowds are protesting a range of economic issues, including bank profits and the power of lobbyists in Washington.

They say they're surprised it's taken so long for more people to take notice.

"It's taken four weeks for people to realize no we really are this upset, we are serious, this is an actual thing. This isn't a fluke," said one protestor.

"About time. Three weeks people have been here. People just taking notice now. More people coming," said another.

Dozens of protestors were arrested earlier this week after police say they rushed officers and tried to push past barricades.

The New York City Police Department says it will continue to accommodate protestors, as long as no laws are broken.

Meanwhile, in the nation's capital today, hundreds of protestors marched on Freedom Plaza to denounce corporate greed.

It follows similar "Occupy Wall Street" type protests held in Pennsylvania, New Jersey, Texas, California and Florida.