MoveOn.org is seeking donations for a new advertisement in which it criticizes John McCainJohn McCainWeek ahead: Pentagon funding in the balance as deadline looms Kasich: 'I think political parties are on their way out' Five fights for Trump’s first year 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 ObamaTrump order could undo designation of national monuments: report Trump will ramp up action on executive orders this week: reports French election: Le Pen, Macron will face off MORE, have been wrong to oppose the U.S. military surge.

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