Electability is the key weakness for Sanders and Buttigieg – the next two races could put that argument to bed

South Carolina in particular will prove difficult ground for the pair, but if they want to win the White House they will both need to do well, writes Chris Stevenson

Bernie Sanders gives his victory speech in Manchester after New Hampshire primary win (AFP/Getty)

Finally, clarity: Bernie Sanders and Pete Buttigieg have momentum, Joe Biden and Elizabeth Warren don’t.

Now comes the big test. The next two contests, the caucuses in Nevada and the primary in South Carolina, have a more diverse electorate than either Iowa or New Hampshire. They will arguably be a more accurate litmus test of electability.