The worst is over for Bernie Sanders. The primaries in the South are finished, and now the Democratic contest heads north to bluer and, for the most part, whiter states.

Sanders should fare better over the second half of the primary season, after black voters gave Hillary Clinton such a big advantage in the first half. But the path to a majority of delegates is, nonetheless, a daunting one. He would need to win the remaining delegates by around a 58-42 percent margin after falling behind again in the delegate count Tuesday night.

Hot streak

It might be very hard for Sanders to win the remaining states by such a margin — though it might not seem that way at first.

The next month features numerous contests where Sanders could be dominant before the calendar turns to those offering Clinton more favorable terrain.

Sanders is clearly favored to exceed his target — the roughly 16-point, 58-to-42 percent margin of victory — in six of the eight contests over the next month. He’s a strong favorite in the caucuses in Idaho, Alaska, Hawaii, Washington and Wyoming. Barack Obama won an average of 72 percent of the vote in these contests in 2008, and so far Sanders is running an average of 4 points behind Obama’s showing in caucus states. Sanders is also a strong favorite in the Utah primary.

Combined, these six states hold 216 delegates. Sanders might hope to win them by a 2-1 margin — perhaps narrowing Clinton’s lead by 65-70 delegates.

In the middle of all of that will be two states that could be slightly more competitive: Wisconsin and Arizona.

Wisconsin is where Sanders really needs to run up the score if he wants to overcome Clinton’s advantage.

Arizona will be important for another reason: It’s a harbinger of how Southern California might vote.

Navigating the coasts

There will still be a fair number of decent opportunities for 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. 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, Sanders is not a favorite to win big in any of those. He’ll need to beat 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. 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 Sanders.

These two factors — affluence and diversity — make it very hard to imagine Sanders sweeping the remaining states, let alone winning them collectively by more than 10 points. Sanders’ best showing in a state where less than 75 percent of voters were white was his 2-point win in Michigan, a less affluent and less diverse state than those along the coasts. He’ll need to do much better.

Sanders would be a clear underdog in Washington, D.C., Maryland and New Jersey, where he could easily lose by more than 20 points. Those big losses will require him to fare even better in the remaining states. But he’s probably an underdog as well in Connecticut, Delaware and New York. Pennsylvania and Rhode Island are perhaps Sanders’ best chances in the Northeast in demographic terms, but Pennsylvania is a closed primary, and neither state looks to give Sanders a particularly lopsided margin.

California prize

Sanders isn’t likely to win big in California, either. Yes, he will most likely sweep the progressive stretches of coastal California — much as he did in rural, western Massachusetts. But the Bay Area’s diversity and affluence make it a tossup region or potentially even one where Clinton would be favored, like the Boston metropolitan area. Much of the central and southern part of the state could lean to Clinton because of a large Hispanic population in the interior and the affluent Democrats along the coast.

California’s primary, on June 7, is at the end of the calendar, so by then we’ll know how well Sanders might need to do in order to make up his delegate deficit. But if Sanders and Clinton split the delegates along the Eastern Seaboard and the territories — which is very generous to Sanders — he might still need to win California by more than 100 delegates — or at least 20 points — to close Clinton’s delegate lead. If he loses along the Eastern Seaboard, as expected, or even in the territories, his goal in California would grow larger very quickly.

More realistically, Sanders will need to win a majority of delegates in the Acela Corridor to keep his required margin of victory in California more manageable. It requires Sanders to win in places where so far he has tended to lose, and often by a lot.