MoveOn.org is seeking donations for a new advertisement in which it criticizes John McCainJohn McCainBush biographer: Trump has moved the goalpost for civilized society White House to pressure McConnell on ObamaCare McCain: Trump needs to state difference between bigots and those fighting hate MORE for not supporting a timetable for the withdrawal of U.S. troops from Iraq.

"John McCain doesn't want a timetable," a narrator says in the ad. "He'll spend hundreds of billions of dollars more to keep our troops in Iraq for years and years."

The narrator adds that Americans and Iraqis, including Iraqi Prime Minister Nouri al-Maliki, have expressed support for a withdrawal schedule.

The Republican National Committee responded to the advertisement by saying that the liberal group and its presidential candidate, Barack ObamaBarack ObamaCongress needs to assert the war power against a dangerous president CNN's Don Lemon: Anyone supporting Trump ‘complicit' in racism DOJ warrant of Trump resistance site triggers alarm MORE, have been wrong to oppose the U.S. military surge.

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