Only dedicated leftists go to see his lame propaganda. Oh and everybody in France.
To be fair, Bowling for Columbine only made $5,885,118 (source: imdb, 2003 oct) in France. Unfortunately it still made about $120 milliion (this figure includes DVD and pay TV sales etc.) overall.
$20 million is huge for a documentary though, and BFC spent most of its time in very limited release. It WAS a success.
Those flops that you list were supposed to do well, had large budgets, etc.
When people say that FH 9/11 will break records, they mean by the standards of a documentary, which rarely make a penny at the box-office.
And I'm not supporting Moore. I hate him.
BTW, considering how his goal is for this film to brainwash people into voting against Bush, my bet is that it'll fail in that department. And you KNOW that Moore and his huge ego are convinced that this movie will convince people to vote against Bush.