On the surface, there’s not a whole lot new here. Biden’s had the strongest national poll numbers for a while now, and Warren and Sanders have been jockeying for second. Sen. Kamala D. Harris (D-Calif.) saw the most important shift in the NBC-WSJ poll, losing more than half of her support. But, then, that’s not really a new dynamic, either.

AD

Looking a bit deeper, though, something else becomes obvious: Warren is in a much better position than it might seem at first glance.

For example, she is now the top choice when poll respondents’ second choices are taken into account. In July, she trailed Biden both overall and when first and second choices were combined. Now she’s the first or second pick of 45 percent of respondents.

The implication of that is significant. The number of people who have Warren as their second pick is growing — so if other candidates stumble, drop out or (later on) lose, Warren will gain more support than other candidates. About a fifth of respondents have Warren as their second choice, while 16 percent say that of Sanders.

It isn’t just that her support is made up of people settling for her, either. Enthusiasm for her candidacy among Democrats has increased steadily in NBC-WSJ polling, while enthusiasm for both Biden and Sanders has stayed fairly flat since July.

These are what a campaign wants to see. Growth. Depth of support. Enthusiasm. There are a lot of undecided voters and a lot of days before people start voting, but you need to see certain trends if you’re going to win. This poll shows positive trends for Warren.

We’ve seen a number of polls recently surveying the national landscape. Biden and Harris have consistent trends in those polls: steadiness for the former and a downward slide for the latter.

But those polls show a muddier picture for Warren and Sanders, two candidates who seem in the abstract to be competing for similar votes. The NBC-WSJ poll shows more space between them than do other polls. On average across these surveys, they’re about 4 percentage points apart.

But that’s just over the short term — and with only one poll after the third primary debate. Looking longer-term, at RealClearPolitics’ average of polls, you can see how we got to this point.

AD

AD

Biden at the top. Harris surging after the first debate — scoring at Biden’s expense both in the debate and in the polls that followed. That early surge for South Bend, Ind., Mayor Pete Buttigieg after his appearance at CNN’s town hall.

And, since early May, a fairly steady upward trend for Elizabeth Warren.

Support in the Democratic primary is more complex than it looks at first. Both Sanders and Warren espouse liberal policies against which Biden pushes back. But Pew Research Center polling released last month showed that the second choice for supporters of Warren was more likely to be Harris than Sanders — and the second choice for Harris was more likely to be Warren. (One implication of that is that Harris’s fade has boosted Warren.) The most common second choice for Biden and Sanders in that poll? “Don’t know.”

AD

AD

There are two significant demographic ways in which Warren’s support differs from Biden’s. He’s got much more support with black primary voters than Warren does (49 percent to 13 percent), while the two are about tied among white voters. He’s also got much more support from moderates (42 percent to 15 percent), while she nearly doubles his support among liberals (36 percent to 19 percent). Sanders, in fact, gets the same level of support among liberals as Biden.

We can visualize those divides like this.

Notice first that there’s clearly a correlation between how well one does with moderates and how well one does with black voters. That’s in part because it’s zero-sum: More support for Biden with those groups means less support for other candidates. It’s also in part because those groups overlap. Black primary voters are more likely to be moderate.

AD

AD

Now notice the size of the circles. For emphasis, we scaled them to the level of support among those ages 65 and up. Biden gets the most support from this group; Sanders, the least.

Across age groups, the support looks like this.

Here, again, you’d rather be Warren than Sanders. The poll weights its results to the population, but younger voters tend to vote less reliably than older ones.