WASHINGTON D.C. – Sunday’s rescheduled dedication ceremony marking the opening of the Rev. Martin Luther King Jr. memorial in Washington D.C. struck a populist tone, as speakers and attendees called the country to action toward fulfilling the dream that King voiced 48 years ago in a speech on the National Mall.

Those on the program who told stories of working with King, those who championed efforts to build the monument, and finally U.S. President Barack Obama, called the tens of thousands of people who attended the ceremony in person and thousands more watching live broadcasts on television and online to action.

“His story tells us that change can come if you don’t give up,” Obama said, drawing on similarities between the obstacles King and activists faced during the tumultuous years of 1960s to challenges in 2011 federal and state politics that, some say, threaten to roll back progress made during civil rights movement.

“As was true 50 years ago, as has been true throughout human history, those with power and privilege will often decry any call for change as “divisive.” They’ll say any challenge to the existing arrangements are unwise and destabilizing,” Obama said.

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“Dr. King understood that peace without justice was no peace at all; that aligning our reality with our ideals often requires the speaking of uncomfortable truths and the creative tension of non-violent protest,” he said.

Speaking directly about the chain of events that led to economic downturn, U.N. Ambassador and member of the civil rights movement Andrew Young called on the public to learn the rules and use them to your advantage.

“You are going to end poverty by learning economics and getting financially literate,” Young said. “Just like we won the battle of voting rights we can win the battle of economic rights.

He also called attendees to action at during this election season. “We need to keep a president in office that has your interests at heart and if we don’t do that this year, God help us.”

While things are better than they were 48 years ago, U.S. Rep John Lewis, who also spoke during that 1963 march on Washington, said there still is work to do.

“We are not there yet. Too many people have been left out and left behind. Let’s use this occasion to go out and finish the task hang in there don’t give up. Keep the faith. Keep your eyes on the prize and walk with the spirit of Martin Luther King Jr.” Lewis said.

The dedication ceremony initially had been planned for August 28 to mark the 48th anniversary of King’s “I Have a Dream Speech” in 1963. Then, organizers projected that more than 250,000 would travel to Washington, D.C. for the dedication, which was canceled due to weather conditions stemming from Hurricane Irene. They lowered their estimate to 50,000 for the October date.

Even as today’s ceremony may have had fewer visitors, several local stations broadcast the dedication live. The foundation also webcast the four-hour ceremony live on its website where it has posted an archive.

The number of people celebrating the MLK memorial this weekend might also be increased by the tens of thousands who “participated in the National Action Network “March for Jobs and Justice,” which included a march to the monument, many of whom did not stay for today’s ceremony.

Members of a half-dozen labor unions, along with supporters of the Occupy Wall Street movement, which has been gaining traction across the country, convened at the monument to participate in the march, which had been previously scheduled August 27th.

Marchers appeared wearing a rainbow of t-shirts from those designed for the August 27th date to those wearing shirts representing affiliation with the Service Employees International Union (SEIU), the Communication Workers of America and the American Federation of State, County and Municipal Employees. They carried signs borrowed from the 1960’s movement as well as new signs calling for jobs and justice.

As collective bargaining comes under threat in several states, labor unions see MLK the man and the monument as a symbol of their continued efforts for employment rights.

“The day before Dr. King was killed, he was part of a strike in Memphis for sanitation workers; those were some of our members,” James Spears an AFSCME field coordinator who traveled from Charlotte, North Carolina said. “We donated to the memorial and we always participate in anything related to MLK.”

“This is just what we needed today,” Maria Kercado, a vice president of the 1199 SEIU, a union that represents health care workers said. “If you look at any of the television clips [of the civil rights movement] you would think it was yesterday.”

At a rally preceding the march NAN founder Al Sharpton told attendees that they were just getting started. He called on people to see the monument as a new symbol for all interested in advancing economic and social justice in America.

“We used to march to the Lincoln Memorial. Now there is a new address in town. We’ve got a new monument,” Sharpton said.