Washington (CNN) Eight days ago, the political world was preparing for one of two scenarios:

1) Bernie Sanders runs away with key Super Tuesday states like California and Texas -- and, in so doing, builds a delegate lead that begins to look insurmountable

2) Joe Biden shows some strength on Super Tuesday, staying within shouting distance of Sanders in the delegate count and setting up an extended delegate battle between the two men.

Instead, a third scenario developed: Biden racked up a series of unexpected wins in places likes Texas, Minnesota and Massachusetts and kept it relatively close in California -- producing a delegate lead for the former vice president heading into Super Tuesday II tomorrow.