“Secretary Clinton cleaned our clock in the Deep South, no question about it,” Bernie Sanders said during Thursday night’s Democratic debate in Brooklyn. “That is the most conservative part of this great country,” he continued. “But you know what, we’re out of the Deep South now. And we’re moving up.”

I have a few problems with this line of argument, which seems to imply that Democratic voters in the Deep South don’t reflect the larger Democratic electorate. (The remarks Thursday night echo previous comments made by Sanders and his campaign.) Consider Sanders’s reference to the term “Deep South,” which traditionally describes Alabama, Georgia, Louisiana, Mississippi and South Carolina: These are five of the only six states, along with Maryland, where at least a quarter of the population is black. Given the United States’ history of disenfranchising black voters — not to mention the importance of black voters to Democrats in November — it’s dicey for Sanders to diminish Clinton’s wins there.

But the Deep South isn’t Sanders’s only issue. His problems in the rest of the South are what really dooms him. Clinton’s largest net delegate gains over Sanders came from Texas (+72) and Florida (+68), two states that are within the South as the Census Bureau (and most other people) define it. Clinton also cleaned Sanders’s clock in Virginia and North Carolina. Overall, Clinton gained a net of 155 delegates on Sanders in the five Deep South states, but she also added 211 delegates to her margin in the rest of the region.

DELEGATE COUNT REGION CLINTON SANDERS NET Deep South* 225 70 Clinton +155 Other Southern states 493 282 Clinton +211 Rest of country 589 745 Sanders +156 Overall 1,307 1,097 Clinton +210 Clinton has dominated Sanders in the South * Alabama, Georgia, Louisiana, Mississippi and South Carolina Source: FiveThirtyEight Delegate Tracker, The Green Papers

In addition to being important to the Democratic Party’s electoral present and future, Florida, Virginia, North Carolina and Texas are quite diverse. They’re diverse ideologically — Miami and Austin aren’t exactly “the most conservative part” of the country — and they’re diverse racially. They contain not only a substantial number of African-Americans but also Hispanics and, increasingly, Asian-American voters.

In fact, these states are among the most demographically representative of the diverse Obama coalition that Clinton or Sanders will have to rely on in November.

Although it will be a couple of decades before the electorate as a whole is majority-minority, the Democratic vote is already getting there. In 2012, only 55 percent of President Obama’s voters were white, according to the national exit poll. Our demographic projections of this November’s electorate, which account for population growth since 2012, calculate that the white share of the Democratic vote will tick down another percentage point, to 54 percent. The rest of the Democratic vote will be black (24 percent), Hispanic (15 percent), or belong to Asian or other races (7 percent), according to our projections.

So let’s take those projections as being maximally representative of the broader Democratic electorate as it stands today. In which primary or caucus states has turnout come closest to those ratios?

In 21 states to have voted so far, we have data on this from exit polls. See here for Virginia, for example, where Democratic turnout was 63 percent white, 26 percent black, 7 percent Hispanic and 5 percent Asian or other when it voted on Super Tuesday. That’s pretty close to the Democratic electorate overall, although with too few Hispanic voters. In the other 29 states — those that haven’t voted yet or where no exit poll was conducted — I’ll estimate the Democratic electorate based on our demographic projections, with an adjustment for the fact that the Democrats who vote in primaries are somewhat whiter than those who vote in November.

Then I’ll calculate the root-mean-square error (RMSE) for each state — a measure of the difference between the demographics of its primary or caucus turnout and the projected Democratic electorate in November. A lower RMSE is better for our purposes, because it means the state’s demographics are more representative of the national Democratic coalition.

DEMOCRATIC PRIMARY/CAUCUS ELECTORATE STATE WHITE BLACK HISP./ LATINO ASIAN/ OTHER RMSE* OUTCOME New Jersey 57% 26% 11% 6% 5% Illinois 58 28 9 5 8 Clinton +2 Florida 48 28 20 5 9 Clinton +31 New York 61 20 16 3 9 Virginia 63 26 7 5 12 Clinton +29 Nevada 59 13 19 8 13 Clinton +5 North Carolina 62 31 3 4 16 Clinton +14 Maryland 47 39 8 6 18 Tennessee 63 32 2 3 18 Clinton +34 Arkansas 67 27 3 3 18 Clinton +37 Michigan 68 23 3 6 18 Sanders +2 Pennsylvania 70 19 8 3 19 California 49 11 23 17 19 Delaware 69 24 3 3 20 Texas 43 19 32 7 21 Clinton +32 Arizona 62 7 25 6 21 Clinton +15 Kentucky 72 21 4 4 22 Missouri 72 21 3 4 22 Clinton +0 Connecticut 74 15 7 3 24 Ohio 74 21 2 3 24 Clinton +14 Alaska 66 5 11 17 25 Sanders +59 Oklahoma 74 14 4 9 25 Sanders +10 Indiana 76 13 8 3 26 Colorado 72 4 16 8 27 Sanders +17 Kansas 78 10 7 5 29 Sanders +36 Washington 74 4 10 12 29 Sanders +46 District of Columbia 45 49 4 2 29 Utah 76 4 11 9 30 Sanders +57 Rhode Island 79 9 8 4 30 Georgia 38 51 7 3 33 Clinton +43 Wyoming 80 4 10 6 33 Sanders +11 New Mexico 45 3 39 13 34 Idaho 80 3 11 5 34 Sanders +57 Minnesota 82 9 3 6 34 Sanders +23 Wisconsin 83 10 3 4 34 Sanders +14 Montana 82 4 6 9 36 Alabama 40 54 1 5 36 Clinton +59 South Dakota 82 3 6 10 36 Nebraska 85 8 3 3 37 Sanders +14 Massachusetts 85 4 6 5 38 Clinton +1 North Dakota 86 4 4 6 39 West Virginia 88 5 5 3 40 Oregon 87 1 4 7 42 South Carolina 35 61 2 2 44 Clinton +47 Iowa 91 3 4 2 44 Clinton +0 Hawaii 45 2 8 46 46 Sanders +43 New Hampshire 93 2 1 4 47 Sanders +22 Louisiana 26 63 8 2 49 Clinton +48 Maine 95 2 1 2 49 Sanders +29 Vermont 95 1 0 3 50 Sanders +72 Mississippi 24 71 1 4 58 Clinton +66 Projected Democratic electorate in November 54 24 15 7 — * Root-mean-square error of turnout as compared with projected Democratic electorate in November Source: Exit polls, FiveThirtyEight demographic projections

The most representative state by this measure is New Jersey. We expect its primary electorate to be about 57 percent white, 26 percent black, 11 percent Hispanic and 6 percent Asian or other, quite close to the national Democratic electorate. New Jersey won’t vote until June 7, although Clinton was well ahead when the last poll was released there in February.

After New Jersey comes Illinois, which Clinton won narrowly — and then Florida, where Clinton won going away. Then there’s New York, which votes Tuesday, and where Clinton is 15 percentage points ahead in our polling average. Virginia, another Southern state, ranks as the next most representative; Clinton won it easily. Then there’s Nevada, another Clinton state, before we go back to the South to North Carolina, also won by Clinton. The next group of four states (Maryland, Tennessee, Arkansas and Michigan) are roughly tied and include some further representation for the South, along with, finally, one state (Michigan) that Sanders won.

In other words, Clinton has won or is favored to win almost every state where the turnout demographics strongly resemble those of Democrats as a whole. This shouldn’t be surprising — Clinton is winning nationally by about 14 percentage points in the popular vote. So if you’re in a state that’s well-representative of Democrats’ national demographics, you might expect her to win it by a solid margin too.

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It’s true that a couple of states in the Deep South, such as Mississippi and Louisiana, rate as being not well-representative by our definition. But overall, that’s more likely to be true of places where Sanders has won. New Hampshire ranks as the 46th most representative out of 50 states (and Iowa ranks 44th — maybe those states shouldn’t hold the first two contests?). Wisconsin, which Sanders won last week, is below average.

And the sort of wishful thinking Sanders is engaged in can cut both ways. Yes, Clinton’s lead would be considerably narrower (although she’d still be winning) without delegates from the Deep South. But what if you excluded delegates from caucuses, where Sanders has gained a net of 150 delegates on Clinton? Without those delegates, Sanders couldn’t even maintain the pretense of a competitive race. Not only are most of those caucus states extremely white and therefore poorly representative of Democrats’ national demographics — many of them (such as Idaho and Nebraska) are also quite red. Furthermore, caucuses tend to disenfranchise voters by making it harder to vote. Our demographic modeling suggests that this has hurt Clinton and that Sanders wouldn’t have won by the same enormous margins if those caucus states had held primaries instead.

But overall, the math is pretty simple. Sanders is winning states that are much whiter than the Democratic electorate as a whole, Clinton is winning states that are much blacker than the Democratic electorate as a whole, and Clinton is winning most of those states that are somewhere in the middle, whether they’re in the South (like Virginia) or elsewhere (like Ohio or Nevada). That’s why she’ll probably be the Democratic nominee.