Navigating the Diverse and Affluent Coasts

There will still be a fair number of decent opportunities for Mr. Sanders after his hot streak is expected to fade. He could win big in North Dakota, Oregon and Montana, or maybe in a few mostly white working-class states like Indiana, West Virginia and Kentucky. The race in New Mexico could be close. Mrs. Clinton is probably the favorite in a few more diverse contests in the territories, like Puerto Rico or Guam, but there’s virtually no information about how these areas might go.

These contests, though, are pretty small. The preponderance of delegates will be from the diverse, affluent, blue states along or near the coasts, like California, New York, New Jersey, Maryland, Pennsylvania, Connecticut and the District of Columbia.

Based on the results so far, including those from Tuesday night, Mr. Sanders is not a favorite to win big in any of those. He’ll need to beat Mrs. Clinton by at least an average of 10 percentage points, and perhaps more if he underperforms in the other states mentioned.

Why? These states aren’t as bad for him as those in the South, but they force him to confront his two weaknesses: diversity and affluence.

The metropolitan East Coast and coastal California are among the most affluent regions of the country. Mr. Sanders has struggled in places with high median incomes, even when those areas have a liberal reputation — like Boston or Northern Virginia, which anchor both ends of the Northeast megalopolis. They provide a pretty good model for what we can expect in between.

The areas he needs to win are also fairly diverse. No, they’re not nearly as diverse as the South. But all of the East Coast states have a roughly average share of black Democrats. Other states, like California, have a large Hispanic population, and it’s still a little unclear how much of a disadvantage that is for Mr. Sanders.