|Liberals are seeking to energise voters ahead of November 2 mid-term elections [AFP]
Thousands of people have gathered in Washington DC for a rally to promote labour and civil rights, and to show support for the Democratic party's agenda.
The demonstration, which brought together hundreds of mostly-liberal and progressive groups on Saturday, was held on the National Mall - the same site as a rally held by conservative Tea Party activists last month.
Billed as "One Nation Working Together", organisers said the event was to draw attention to civil rights issues, economic policies and education reforms.
Richard Trumka, president of the AFL-CIO - the country's largest federation of trade unions - urged the gathered crowd to "promise that you'll make your voices heard, for good jobs and justice and education today and on election day".
A spokeswoman for the organisers estimated attendance at between 175,000 and 200,000 people, stretched from the Lincoln Memorial to the end of the National Mall's Reflecting Pool.
One sign in the crowd read "Axis of Ignorance = Tea Party, Republicans, and Fox News," referring to the conservative US news channel. Another read "Stop the racist hate, Muslims are welcome here."
Conservative groups made their show of strength in Washington on August 28, headed by radio and TV commentator Glenn Beck, also drawing tens of thousands of supporters.
"This is a defining moment in America ... this is no time to back down. This is time to fight for America"
Ed Schultz, MSNBC and radio host
Saturday's demonstration, in parternship with more than 400 organisations, ranging from faith-based groups to gay rights activists and environmentalists, was meant to serve in part as a counter-rally to Beck's ahead of US mid-term congressional elections.
Al Sharpton, a prominent civil rights activist, told the rally to consider the November polls a "mid-term exam".
"We've got to go home, and we've got to hit the pavement. We've got to knock on doors. We've got to ring that church bell. We've got to get ready for the mid-term exam," he said.
Lberal commentator Ed Schultz, of the US channel MSNBC, sought to rouse the crowd with fiery rhetoric, even co-opting Beck's "take back our country" rhetoric.
"This is a defining moment in America ... this is no time to back down. This is time to fight for America," he said.
"This march is about the power to the people. It is about the people standing up to the corporations."
With Democrats in the White House and in control of congress, Republicans have sought to take advantange of the country's flagging economy to try to build momentum.
Some who supported Barack Obama, the US president, in the 2008 election have expressed dismay at how slow he has been to implement the changes he campaigned on. But a shift towards a Republican-controlled congress could further sidetrack or slow Obama's legislative agenda.