Tuesday night’s surprise win in Michigan for Bernie Sanders was a humbling night for political prognosticators.

He had trailed in pre-election polls by around 20 points — a bit less in some polls, a bit more in others. My colleague Nate Cohn has written an excellent post-mortem; Nate Silver of FiveThirtyEight declared it to be “among the greatest polling errors in primary history.”

It’s worth juxtaposing this with a less-noticed fact: Hillary Clinton beat the (admittedly sparse) polls in Mississippi by an average of 22 points. Those polls had predicted Mrs. Clinton to win, but by a much smaller margin than 66 points. It may be less embarrassing for pollsters when they miss the margin badly but correctly pick the top vote-getter, but when delegates are awarded proportionately, it’s no less consequential.

Perhaps we shouldn’t be surprised: Polling response rates, particularly for robocalls, are down around the single digits. Some pollsters still haven’t fully adjusted to the fact that landlines are now a historical curiosity in many households.