Levitating a Federal Building

How many people does it take to levitate the U.S. Mint building in Denver? Apparently more than 75. National Journal's Convention Daily reports that an effort by that number of protestors at the Democratic National Convention to encircle the building and raise it off the ground -- similar to a protest years ago at the Pentagon -- didn't exactly work out.

Maybe the problem was that the protestors turned out to be "easily outnumbered by police." Or maybe it was the weight of all the coins.