Television comedians Jon Stewart and Stephen Colbert drew tens of thousands of people to the National Mall in Washington DC promising to skewer partisan politics three days before contentious US elections.
The 'Rally to Restore Sanity and or Fear' started off as part slapstick comedy show and part outdoor festival concert.
Comedian Jon Stewart opened the festivities by declaring that 'ten million' people showed up, representing all ethnic groups in the US.
The rally, widely viewed as a response to August's 'Restoring Honor' rally organised by conservative talk show host Glenn Beck, blurred the lines between satire and political activism.
The Comedy Central hosts, who target Washington and its politicians regularly in their mock newscasts, avoided overt references to the Democrats and Republicans battling for control of Congress and governorships in Tuesday's elections.
The show was opened by recording star John Legend, who performed at an inaugural concert for President Barack Obama in January 2009 and Philadelphia hip-hop/funk band The Roots.
The Glenn Beck rally in August, which also featured 2008 Republican vice presidential candidate Sarah Palin, drew many people associating themselves with the Tea Party.
It was peppered with speeches about God and country and tributes to the US military, including wounded veterans of wars in Iraq and Afghanistan.
Meanwhile, President Barack Obama has warned that if Republicans prevail in next week's congressional elections they could roll back his agenda, as he sought to rally fellow Democrats to the polls in a final campaign push.
