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Poll of the week

Earlier this week, I looked at national surveys to see what’s behind Sen. Elizabeth Warren’s rise in the polls, but now let’s zoom in on the early primary states — Iowa, New Hampshire, Nevada and South Carolina — to see what’s happening there.

This week we have a new Fox News poll of South Carolina that shows former Vice President Joe Biden still retains a formidable lead there at 41 percent (Warren was in second at 12 percent) despite Warren’s gains at the national level. In Iowa and New Hampshire, recent surveys more closely mirror the overall national picture — Warren has gained while Biden and Sen. Bernie Sanders have slipped. But there’s also evidence that someone like South Bend, Indiana, Mayor Pete Buttigieg may be underestimated in national polls.

To see what’s happened in the early states since August, I averaged all state-level polls taken between the second debate (July 30-31) and the third debate (Sept. 12) and compared that to an average of all state polls fielded since the third debate for the five candidates currently sitting at the top of the polls: Biden, Warren, Sanders, Buttigieg and Sen. Kamala Harris.

And in some states, there weren’t a ton of polls during these two time periods, but we did have at least two polls for each state before and after the third debate.

First up, in Iowa, you can see a real change in the nature of the race — Biden previously led by about 3 percentage points, but now Warren has moved ahead. Sanders also slipped about 5 points, so instead of rivaling Warren for second place as he did before the third debate, he’s now in a race for third. He’s about on par with Buttigieg, who now has double-digit support in the state, although the mayor enjoyed a pretty strong standing there before the debate, too. Harris slipped in Iowa, dropping 3 points, which is similar to her performance in the three other early states.

Warren has edged ahead of Biden in Iowa Average of Iowa polls for the five leading Democratic presidential candidates, before and after the third debate Poll Average Candidate Before Third Debate After Third Debate Change Elizabeth Warren 21.3 23.0 +1.7 Joe Biden 24.7 20.3 -4.3 Bernie Sanders 17.3 12.0 -5.3 Pete Buttigieg 9.3 11.3 +2.0 Kamala Harris 8.3 5.3 -3.0 Our “before third debate” average includes three polls taken from Aug. 1 to Sept. 11; the “after third debate” average also includes three polls. We excluded head-to-head and open-ended polling questions. Source: Polls

Next up, in New Hampshire, the story is pretty similar to what we saw in Iowa: Warren’s numbers improved, giving her a narrow lead. In fact, she’s gone up nearly 10 points, far more than in Iowa. However, unlike in Iowa, Biden’s numbers have gone up, too. They didn’t rise as dramatically as Warren’s, but the jump has helped him stay close to Warren in the nation’s first primary state. Meanwhile, Sanders’s slide in New Hampshire has been particularly large, going from a near-tie for first with Biden to 15 points behind Warren. And as in Iowa, Buttigieg is now closer to Sanders than Sanders is to Warren or Biden, while Harris has fallen to the low single digits.

Warren surged in New Hampshire, but Biden gained too Average of New Hampshire polls for the five leading Democratic presidential candidates, before and after the third debate Poll Average Candidate Before Third Debate After Third Debate Change Elizabeth Warren 17.6 27.0 +9.5 Joe Biden 21.6 24.3 +2.7 Bernie Sanders 20.9 12.0 -8.9 Pete Buttigieg 7.0 9.7 +2.7 Kamala Harris 6.9 4.0 -2.9 Our “before third debate” average includes six polls taken from Aug. 1 to Sept. 11; the “after third debate” average includes three polls. We excluded head-to-head and open-ended polling questions. Source: Polls

To some extent, Warren’s uptick in Iowa and New Hampshire isn’t that surprising given her strength with white college-educated voters and, as I wrote on Monday, her increasing support from whites without a college degree. After all, 85 to 90 percent of Iowans and New Hampshirites are white. A lot of this can explain why Buttigieg is doing so well there, too, as he also mainly attracts support from white voters, particularly college-educated ones. That said, his performance in these two early states still stands out in comparison to his mid-single-digit standing in the national polls. And this could be a promising sign for Buttigieg given the influence these two states can have on the presidential primary process — once voting begins, he could be positioned for a strong start that could take his campaign to the next level, especially in light of his prodigious fundraising.

But in our next two early-voting states — Nevada and South Carolina — the picture gets a little fuzzier because we don’t have as many polls. Biden continues to lead the pack in both states (although in Nevada, the race looks more like a three-way tie), but there just hasn’t been as much consistent polling in either state. And that’s a problem, because even though both states come later in the calendar, they are much more racially and ethnically diverse than either Iowa or New Hampshire. So these states could offer important insight as to how other more-diverse states may be leaning, as New Hampshire and Iowa look less and less like the Democratic Party.

For Nevada, we had three surveys prior to the third debate and two after, and they showed a tight three-way race among Biden, Warren and Sanders that got even closer after the third debate. Both Biden and Sanders lost some support, but Warren didn’t emerge as the beneficiary.

It’s a three-way race in Nevada Average of Nevada polls for the five leading Democratic presidential candidates, before and after the third debate Poll Average Candidate Before Third Debate After Third Debate Change Joe Biden 26.0 22.6 -3.4 Elizabeth Warren 18.7 18.7 0.0 Bernie Sanders 20.3 18.1 -2.2 Kamala Harris 8.3 4.4 -3.9 Pete Buttigieg 5.3 3.7 -1.6 Our “before third debate” average includes three polls taken from Aug. 1 to Sept. 11; the “after third debate” average includes two polls. We excluded head-to-head and open-ended polling questions. Source: Polls

And in South Carolina, where we had two polls before the third debate and four polls after, it seems as if no one has been able to make a serious dent into Biden’s support, although he did see a slight dip in his numbers. Biden’s continued strength among black voters in the state has made South Carolina a crucial firewall for his campaign, especially if things go poorly for him in the earlier contests. Sanders’s decline in South Carolina has also helped make Warren a clear second-place contender (even though she, like Biden, saw a slight dip in her numbers after the third debate).

Biden continues to dominate in South Carolina Average of South Carolina polls for the five leading Democratic presidential candidates, before and after the third debate Poll Average Candidate Before Third Debate After Third Debate Change Joe Biden 39.5 37.8 -1.8 Elizabeth Warren 15.5 14.8 -0.8 Bernie Sanders 17.0 9.0 -8.0 Kamala Harris 9.5 4.5 -5.0 Pete Buttigieg 4.5 3.3 -1.3 Our “before third debate” average includes two polls taken from Aug. 1 to Sept. 11; the “after third debate” average includes four polls. We excluded head-to-head and open-ended polling questions. Source: Polls

As always, though, things could shift in the coming weeks. After all, we’ve got the fourth debate coming up on Oct. 15, which could help Sanders or Harris recover to some extent, though we don’t know yet what the polling fallout may be from Sanders’s recent heart attack. But for the moment, what we do know is that the early-state polls in New Hampshire and Iowa look favorable for Warren, while Biden still holds the lead in South Carolina and Nevada. We shouldn’t sleep on Buttigieg, either — although both he and Warren have a lot of work to do to win over more voters of color.

Other polling bites

Trump approval

According to FiveThirtyEight’s presidential approval tracker, 42.0 percent of Americans approve of the job Trump is doing as president, while 53.7 percent disapprove (a net approval rating of -11.7 points). At this time last week, 41.2 percent approved and 53.9 percent disapproved (for a net approval rating of -12.7 points). One month ago, Trump had an approval rating of 41.0 percent and a disapproval rating of 54.1 percent, for a net approval rating of -13.1 points.

Generic ballot

In our average of polls of the generic congressional ballot, Democrats currently lead by 6.1 percentage points (46.2 percent to 40.1 percent). At this time last week, Democrats led by 6.9 percentage points (46.9 percent to 40.0 percent). At this time last month, voters preferred Democrats by 6.5 points (46.3 percent to 39.8 percent).