No chance. It will pass up some other fiat currency way before the dollar ever see's bitcoin as a replacement. The government and dirty politicians will make sure that never happens under their watch.
That is right for the short term. When the bitcoin infrastructure is built, it will be used more widely, there is a chance to replace dollar.
Whatever adoption Bitcoin is enjoying in the coming years, there will never be a time where Bitcoin replaces the Dollar or any other fiat currency.
It's impossible. Only governments have the ability and the power to replace or change something in their system.