That said, there are also some reasons to think that this slip in Biden’s overall approval rating might not be a blip.

The biggest reason is that independents may be souring on Biden — and it’s not clear that it’s just his handling of the coronavirus driving it. Biden’s ratings among independents have fallen in recent weeks — a sample of polls conducted since early July by Morning Consult, The Economist/YouGov and Ipsos suggests Biden’s approval with this group has fallen by an average of 2 to 4 percentage points in recent weeks. But Biden had already been slowly losing ground among independents. For instance, Biden’s approval among independent voters in Morning Consult’s polling has trended downward since he took office, from around the low 50s to the low 40s. That’s a very slow descent over the past eight months, but it’s also a trend that predates the surge in American cases of the delta variant.

It’s also possible that concerns about the economy have played a role in Biden’s decline. Recent surveys suggest Americans are particularly worried about inflation, for instance, which has shot up in recent months. In fact, about one-third of registered voters named inflation as their top economic concern in an early August survey by The Hill/HarrisX, and 86 percent of Americans told CNBC/Hart Research/Public Opinion Strategies in late July that they’d taken at least one action to combat the rise in prices, such as reducing their spending on discretionary items or saving less money. Biden’s approval on his handling of the economy has ticked down slightly in recent surveys, too, including a Fox News poll last week that found approval of his handling of the economy at 47 percent, down from 51 percent in June.