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More than 400 progressive and civil rights groups marched Saturday on the Lincoln Memorial in support of jobs, education and justice -- seeking to tap into the same anger that fuels the Tea Party movement.

Organizers, including the NAACP, La Raza and Code Pink, called it the most diverse march in history as they tried to rally their base around Democrats struggling to keep power on Capitol Hill.

"We are together. This march is about the power to the people," said MSNBC host Ed Schultz. "It is about the people standing up to the corporations. Are you ready to fight back?"

In a fiery speech that opened the "One Nation Working Together" rally on the National Mall, Schultz blamed Republicans for shipping jobs overseas and curtailing freedoms. He borrowed some of conservative Fox News host Glenn Beck's rhetoric and vowed to "take back our country."

"This is a defining moment in America. Are you American?" Schultz told the raucous crowd of thousands. "This is no time to back down. This is time to fight for America."

The head of the NACCP said the march is not an alternative to the Tea Party but an antidote.

"We're all working for the same purpose, the same mission," said the NAACP's Jamie Branch. "Everybody wants jobs. Everybody wants health care. It's just a way of going about doing things and if we all come together like all these people are, it will benefit everybody."

With a month of campaigning to go and voter unhappiness high, the Democratic-leaning organizers hope the four-hour program of speeches and entertainment energizes activists who are crucial if Democrats are to retain their majorities in the House and Senate. The national mood suggests gains for the GOP, and Republicans are hoping to ride voter anger to gain control of the House and possibly the Senate.

But organizers insist this rally is not partisan -- echoing Beck, who said described his own Lincoln Memorial rally in August as nonpartisan.

Organizers said Saturday their message is about job creation, quality education and justice. However, the largest organizations, such as the AFL-CIO and the Service Employees International Union, tend to back Democratic candidates.

And the first speakers hardly shied from criticizing Republicans.

"They want to change this country," Schultz warned participants of Republicans.

More than 400 organizations -- ranging from labor unions to faith, environmental and gay rights groups -- partnered for the event, which comes one month after Beck packed the same space with conservatives and tea party-style activists.

Beck and former Alaska Gov. Sarah Palin gathered near the Lincoln Memorial on the anniversary of Martin Luther King Jr.'s "I Have a Dream" speech to urge a vast crowd to embrace traditional values. Though also billed as nonpolitical, the rally was widely viewed as a protest against the policies of President Obama and congressional Democrats.

One Nation organizers said they began planning their event before learning about Beck's rally, and said Saturday's march is not in reaction to that.

Obama was spending the weekend at Camp David, the presidential retreat in Maryland.

Fox News' Molly Henneberg and The Associated Press contributed to this report.