How Is Joe Biden Remaking The 2016 Primary Map?

Graphics by Yutong Yuan

The 2020 Democratic primary is on the backburner. Many states have postponed their primaries because of the spread of the coronavirus, but there isn’t much question as to who will win the nomination.

For all intents and purposes, former Vice President Joe Biden is now the presumptive nominee. He has amassed a more or less insurmountable lead in the pledged delegate count, 1,201 to Sen. Bernie Sanders’s 888, according to ABC News. And he’s done it by winning places Sanders won handily in 2016 and even overperforming Hillary Clinton in some areas she won four years ago.

So let’s take a deep dive into Biden’s map so far and look at where he’s outperformed Clinton and where he’s gained ground from Sanders. We dug into county-level data for the 18 states that have already held primaries¹ and compared their 2020 and 2016 results.

Bottom line: Biden held onto much of the turf that Clinton won in 2016, but he also captured a lot of territory that Sanders carried four years ago. We found that much of Biden’s success can be explained by his dominance in areas with larger shares of white voters without a college degree. Biden has also done better among college-educated white voters than Sanders has in 2020 and better in rural areas than Clinton did in 2016.

Let’s start with the topline comparisons between the 2020 Democratic primary and the 2016 race between Sanders and Clinton. In the map below, you’ll see counties color-coded by whether:

1. Clinton won them in 2016 and Biden in 2020.
2. Sanders carried them in both 2016 and 2020.
3. Sanders won them in 2016 and Biden in 2020.
4. Clinton won them in 2016 and Sanders in 2020.
5. A candidate other than Biden or Sanders won them in 2020.

In fact, Biden finished first in 93 percent of the counties that Clinton won in 2016. On top of that, he won 83 percent of the counties that Sanders carried in 2016, meaning that Sanders held onto very little of what he won last time around. These gains were especially apparent once Biden and Sanders moved into the head-to-head portion of the race, starting with the primaries on March 10.² In the six states that voted on March 10 or later — Arizona, Florida, Illinois, Michigan, Mississippi and Missouri — Sanders won about half of all counties in those states in 2016, but just three in 2020. Although Sanders did win some places that Clinton carried in 2016, he gained relatively little ground outside of California and Texas, and Sanders’s additions in Texas weren’t enough to help him win there.

The difference between Biden and Clinton’s performance is most obvious in areas with sizable shares of white voters who don’t have a college degree. And as you can see in the chart below, the larger the share of a county’s population that is white without a college degree,³ the better Biden tended to perform compared to Clinton, even when Biden’s vote share in that particular county was smaller than Clinton’s.⁴

Exit polls also underscore this trend, especially if we look at the race once the candidate field had winnowed after the February contests. In the 10 states that voted in March for which we have both 2016 and 2020 exit poll data,⁵ Sanders edged out Clinton among white voters without a college degree in 2016, 54 percent to 44 percent. But in 2020, Biden beat Sanders, 40 percent to 33 percent in those same states.⁶

Even though we don’t have complete exit poll data from Michigan, the result there may best capture just how much ground Biden made up with white voters without a college degree, compared to Clinton’s performance with this group in 2016. Four years ago, Sanders won the state by about 1 point in a huge upset. He carried 73 of 83 counties while winning 57 percent of white voters without a college degree, per the 2016 exit poll. But in 2020, Biden won every county in Michigan en route to beating Sanders by nearly 17 points. The partial Michigan exit poll also found the former vice president won a majority of white voters without a college degree.

But it wasn’t just white voters without a college degree with whom Biden overperformed. He also did well with college-educated white voters, although Clinton also did well with this group in 2016, so Biden’s gains over Clinton are less pronounced.⁷ In fact, Biden’s gains here may actually be better explained by Sanders’s comparatively poor performance among this demographic. As the share of the college-educated white population in a county increased, the worse Sanders tended to perform compared to his 2016 vote share.⁸

Take Sanders’s performance in Chittenden County, Vermont, where Sanders’s hometown of Burlington is located. Nearly half (47 percent) of the county’s population is white and has a college degree, and although Sanders still easily won there, his vote share fell more than 30 points (85 percent in 2016 to 52 percent in 2020). Or if we consider states that voted once it became a two-horse race, take Boone County, Missouri, home to the University of Missouri, where a sizable portion of the population is college-educated and white (39 percent). There, Sanders dropped 16 points, from 61 percent in 2016 to 45 percent in 2020.

The exit polls also point to Sanders’s loss in support among white college-educated voters. In the 10 states that voted in March for which we had both 2016 and 2020 exit poll data, Sanders narrowly lost to Clinton among white voters with a college degree, 47 percent to 51 percent. In 2020, he trailed Biden 23 percent to 39 percent.⁹

One last area we want to point to on Biden’s map: His strength in less populous areas relative to Clinton. We categorized counties by whether they belonged to a metropolitan area with at least 500,000 people,¹⁰ and found that Biden had a larger margin over Sanders in more sparsely populated areas than Clinton did in 2016. Biden led Sanders in these areas, 46 percent to 28 percent — an 18-point lead. Though Clinton also led Sanders in these areas in 2016, 53 percent to 43 percent, her lead was much smaller — 10 points.

Biden was a bit behind Clinton in counties within large metro areas: She edged Sanders 57 percent to 42 percent, while Biden led Sanders 42 percent to 31 percent. But in contests on or after March 10 when the 2020 primary became more of a two-person race, Biden outpaced Clinton in a number of large metro counties in Illinois, Michigan and Missouri. However, Biden still fell short of Clinton in Arizona and Florida, which might speak to his lower support among Latino voters. (Biden’s vote share in Mississippi was nearly even with Clinton’s 2016 performance.)

On the whole, Biden has essentially matched Clinton’s strength in bigger metro areas while improving on her performance in less populous places. His strength among white voters without a college degree helps explain much of his success, especially given that they’re more likely to live in rural areas. Biden’s relatively strong performance among college-educated white voters also helped him build a winning coalition across the country. Meanwhile, Sanders’s weaker showing among white voters regardless of education levels made it difficult for him to win as the candidate field narrowed in 2020. The end result? A race that’s just not as competitive as the 2016 Democratic primary.

Likhitha Butchireddygari contributed research.

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