This poll feels like an outlier
The survey was conducted Aug. 17-20 using a voter list of 801 registered voters nationwide. It was carried out by Braun Research and has a simple sampling error of plus or minus 3.5 percentage points at a 95 percent confidence interval.
The bulk of the fieldwork took place before the Democratic Party convention so it is possible the next poll from this pollster could see an even bigger Harris lead.
TSE