On the first day of the 2020 Democratic National Convention, such as it is, Joe Biden continues to enjoy a national lead over Donald Trump in every published poll. In the RealClearPolitics database, you have to go back to an Emerson poll in February to find a survey in which Trump actually led.
In the RCP polling averages, moreover, Biden’s current lead, at 7.7 percent, is close to where it has been for much of the summer. It was below 7 percent just two weeks ago. Team Trump may note that it’s not far above Clinton’s lead in the same averages (5.8 percent) at this point in 2016, but the polling in that race was regularly more turbulent (Clinton had been trailing as recently as July 27, and led by 7.9 points on August 8).
But if Biden’s lead in the polling averages is pretty steady, Trump can point to one recent high-quality poll in which he’s made some pretty big gains: A new CNN national survey shows him trailing Biden by a relatively narrow four-point margin (50/46), which actually matches the poll’s margin of error. More significantly, it shows a big swing toward Trump since CNN’s last national poll in early June, which showed Biden leading by 14 points (55/41), with the president gaining among men, independents, and even among Republicans.
But the CNN poll may just show why it’s important to look at averages. Three other respected national surveys released in the last week, utilizing the preferred live-interview methodologies, had Biden maintaining more comfortable leads. ABC–Washington Post showed Biden up 12 points (10 points among likely voters); NBC News–Wall Street Journal gave Biden a nine-point lead, and Fox News a seven-point lead. And a CBS–YouGov online tracking poll of a probability-based national sample showed Biden up by ten points. CNN looks to be an outlier, at least this time.
The measurement of Trump’s popularity that may be more reliable than horse-race polls continues to oscillate slowly within a narrow band: his job approval rating. It’s currently at 43.1 percent at RCP and 42.2 percent at FiveThirtyEight (which weights polls for accuracy and adjusts them for partisan bias). His ratings are a couple of points higher than a month ago, but still several points below his late-March, early April, and early pandemic highs.
It’s unlikely Biden will get much if any of the traditional post-convention polling “bounce,” since it’s a virtual convention with relatively light media coverage, followed immediately by the GOP convention. Partisan polarization also reduces polling variation generally by reducing the number of swing voters changing their minds.
For now, Biden is still in the driver’s seat, and Trump is still facing the drag of persistently low assessments of his leadership on COVID-19 (his average approval ratio on that metric at RCP is currently 40/58). The race is far from over, but one favorable poll for Trump isn’t enough to conclude that its trajectory has changed.