What Went Down In The Indiana Primary

For some perspective on Indiana, our final polling average had Clinton up by around 7 percentage points. By comparison, her lead in Michigan was in excess of 20 points — about three times as high. That was a historic upset for Sanders; this would be a pretty normal primary miss. If Sanders wins Indiana, it would be the second state so far — after Michigan — where the FiveThirtyEight polling average has miscalled the winner.

So it looks like the polls are going to be wrong on the Democratic side in Indiana? Where will this stack up in terms of polling misses this year?