58 dnc unfurled  2020
CNN  — 

Former Vice President Joe Biden headed into the Democratic National Convention with a clear lead over President Donald Trump. But even as Biden continued to hold about a 9-point advantage in an average of CNN approved live interview polls conducted in August, a weak spot remained clearly visible for Biden: Black voters.

Although Black voters propelled Biden to victory in the primary, his lead with them continues to be noticeably smaller than Clinton’s edge at the end of the 2016 campaign.

One clear way to deduce if Biden had a successful convention is if he starts at least matching Clinton’s numbers with Black voters.

The convention was, of course, the first big opportunity for Biden to share the limelight with his running mate, California Sen. Kamala Harris. Harris, the first Black and South Asian woman to be on a major party ticket, was selected in part because of the clamoring among the base for Biden to pick a woman of color as his running mate.

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Biden will take any help he can get with Black voters.

So far this month, there have been five live interview polls for which I could attain a Black voter crosstab: ABC News/Washington Post, CNN/SSRS, Fox News, Marist College/NPR/PBS NewsHour and NBC News/Wall Street Journal. While none of the polls individually have a sample size to be too reliable, aggregated together they tell a pretty clear story.

Biden is ahead among Black registered voters by 67 points on average and 71 points in the median of these polls. That’s a sizable advantage.

It’s actually slightly less though than the 75-point lead he had with Black registered voters when I looked at the average of polls taken in late May through mid-July. While we can’t be sure that Biden’s actually doing worse with Black voters than he had previously, given sample size restrictions, it’s quite clear he isn’t doing better than he was earlier in the summer. As far as I can tell, Biden’s lead with Black voters is currently at one of its lowest levels of the 2020 campaign.

More interestingly, his support among Black voters is quite clearly smaller than Clinton’s 79-point margin in the final registered voter polls of 2016.

An 8-point shift among Black voters (i.e. moving from a 79-point win for the Democrats to a 71-point win) could be a huge deal if applied to the swing states. It could shift the overall margin in a number of states (like Michigan and Florida) by a point. Remember Clinton only lost Florida by a little more than a point and Michigan by just 0.2 points.

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Biden’s relative difficulty seems to be because of younger Black voters. When I aggregated across CNN polls this year, Biden was dominating with Black voters age 50 and older. He led them by about 85 points. Biden’s margin was only about 65 points among Black voters under the age of 50. The sample sizes (north of 300 for the under 50 subset and 400 for the age 50 and older group) are large enough that we can feel pretty certain that there’s an age divide in Black voter preference.

This large age gap among Black voters is consistent with an earlier study done by political scientists Dan Cox and Rob Griffin.

Four years ago, there was no such age gap in the pre-election polling. Trump basically was stuck at 5% or slightly less no matter the age group of Black voters. That is, Trump’s doing no better than four years ago among older Black voters. (The age gap was somewhat prevalent in some other data such as the Cooperative Congressional Election Study, though not anywhere to this degree.)

Still, Biden’s problems with younger Black voters does make some sense in the context of history. We saw it throughout the primary season. Biden would routinely lose Black voters under the age of 30 to Vermont Sen. Bernie Sanders, while crushing him among Black voters 65 years and older.

Over all of the primary contests where at least 5% of Democratic primary voters were Black, Biden won an average of 78% among Black voters 65 years and older. He managed 29% on average among Black voters less than 30 years old. That’s about a 50-point gap in support.

Part of Biden’s issue may be that younger Black voters are less likely than older Black voters to be religiously affiliated. Unlike among White voters, where evangelicals are far less likely to be Democratic than White voters overall, Black Protestants are actually more likely to be Democratic than Black voters overall.

It should also be said the Trump campaign has made clear efforts to reach out to Black voters.

Also potentially worrying for Biden is that Black voters don’t seem nearly as likely to turn out in the fall as White Americans. Across the last three ABC News/Washington Post polls, for example, White Americans were 4 points more likely to say they were certain to vote. In CNN polling this summer, White voters were about 10 points more likely than Black voters to say they were extremely enthusiastic about voting.

In a study of the six closest states Trump won in 2016, the New York Times/Siena College poll had White voters as 4 points more likely to say they were almost certain to vote than Black voters. (Their national poll had White voters 15 points more likely to say they were almost certain to vote.) White voters were about 10 points more likely they were absolutely certain to vote in Wisconsin polling this year by the Marquette University Law School.

This follows the 2016 campaign in which Blacks were 5 points less likely than Whites to turn out, after being 6 points more likely in 2012.

It’s not clear at all if Biden will be able to reverse Clinton’s slide relative to Barack Obama in this regard.

Biden will likely be happy to start matching Clinton among Black voters in terms of support. Whether he’ll end up doing that, we’ll have to wait and see.