Frank Bruni: Bernie Sanders prevails. Cue the party panic.

The Democratic race was messy going into New Hampshire. It’s even messier as it moves on.Yes, Bernie Sanders won the state’s primary on Tuesday night. And that victory, coming on the heels of his functional tie with Pete Buttigieg in the dysfunctional Iowa caucuses last week, makes him the indisputable front-runner for the Democratic nomination.But look at how closely behind him Buttigieg finished, despite furious attacks from Sanders and other rivals over recent days. Look at the su