Rev. Al Sharpton announces details of a march for "Jobs Justice" to be held Oct. 15 on the National Mall in Washington. (Evan Vucci/AP)

The Rev. Al Sharpton is planning a march next month to bolster the president’s jobs bill and bring attention to the plight of the unemployed.

The march, which will draw labor groups and civil rights organizations, is expected to bring thousands to the Mall on the day before the new memorial honoring the Rev. Martin Luther King Jr. is officially dedicated, organizers said.

Sharpton — who is a civil rights activist, nightly TV host and staunch Obama ally — painted the march on Oct. 15 as an answer to Obama’s call to mobilize behind the jobs proposal he introduced two weeks ago and also as a refutation of the president’s critics.

“We will bring forth the masses who have not been heard in the midst of the jobs debate,” said Sharpton, who was flanked by leaders of the National Education Association, NAACP and other groups. “As the president fights for a jobs act, as supercommittees meet, they need to hear marching feet. This is to send a message to Congress.”

The march, which will count on the large ranks of union members, will bring “drama” to the jobs debate, Sharpton said. He said he will give a speech, along with union leaders and the presidents of the NAACP, the National Urban League and the National Council of La Raza.

Sharpton, who has organized marches on a range of issues through the years, held his last march in Washington just before television host Glenn Beck held a large rally on the Mall on the anniversary of King’s “I Have a Dream” speech.

The October march, which was originally scheduled for the August weekend of the dedication of King’s memorial, was delayed because of a looming hurricane. Members of the organizing committee said they want to underscore their support for the president’s jobs plan.

“We want to do something to show that we want to do something about these growing inequalities,” said Randi Weingarten, president of the American Federation of Teachers.

Hilary Shelton, director of the NAACP’s Washington bureau, said the march was about showing that “the American Jobs Act is the solution.”

The march also falls in line with the Obama campaign’s ramp-up for the 2012 election as the president attempts to consolidate support among his base.