The conventions changed nothing
By 
All of the punditry about how the race might be transformed because imaginary voters might like Donald Trump’s endless, poorly written and delivered convention speech, wasted again:
The Republican National Convention provided the president with four nights of free network airtime, and thus, a unique opportunity to change the shape of the presidential race. Post-RNC polling suggests that he failed to do so.
Before the Democrats kicked off convention season on August 16, Biden led Trump by 7.7 points in RealClearPolitics polling average and by 8 in FiveThirtyEight’s; now, those figures are 7.2 and 7.3 respectively. This represents an improvement on Trump’s part, but one small enough to be mere statistical noise. Given that Trump likely needs to get Biden’s national lead down beneath 3 points in order to have a 50-50 shot of winning the Electoral College, a convention bounce that leaves the Democratic nominee ahead by more than seven is bad news for the commander-in-chief.
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On August 23, a police officer shot an unarmed Black man in the back seven times in Kenosha, Wisconsin. A mix of nonviolent protests, riots, and looting ensued. Days later, a 17-year-old Donald Trump enthusiast traveled to Kenosha from Illinois with an AR-15 rifle (that he had no legal right to possess) with the avowed aim of upholding “law and order.” He ended up shooting two people to death. Trump then defended the teenage vigilante.
And, for whatever reason, many Democrats concluded that all this would redound to the benefit of a president who had vowed in 2016, “When I take the oath of office next year, I will restore law and order to our country. Believe me.”
To be fair, when your party is leading by a comfortable margin, any potentially transformative media event is undesirable. And historically, the Republican Party has boasted an advantage on the issue of public safety. If anything could plausibly displace the pandemic from the front of marginal Wisconsin voters’ minds, it might be a sudden increase in crime and urban unrest. And unlike in the recent past, rising murder rates are a genuine policy problem in 2020 across many metro areas.
Still, the notion that a sitting president could mount a comeback by arguing that America is descending into anarchy on his watch was always a bit counterintuitive. And surveys taken since the unrest in Kenosha indicate that “if Joe Biden is elected, things will be as bad as they are now” isn’t actually a winner for Mr. Trump.
Morning Consult’s most recent poll finds that voters trust Biden over Trump on the issue of public safety by a 47 to 39 percent margin, while giving the Democrat an even larger edge on “race relations.”
Levitz points to some other problems for Trump: Biden has raised tons of money as is outspending him on ads by a substantial margin, and the economy is likely to get worse before it gets better because of Republican refusal to pass a relief bill while the pandemic rages. And this might be the most important difference:
CNN poll in early Sept. 2016: Trump leads Clinton by 2 points. He leads Clinton by 15 points (!) on who’s more honest and trustworthy.
CNN poll in early Sept. 2020: Biden leads Trump by 8 points. He leads Trump by 17 points (!) on who’s more honest and trustworthy.— Sahil Kapur (@sahilkapur) September 2, 2020
In 2016, Trump was actually seen by voters as the more honest candidate. Another way of putting this, then, is that unlike in 2016 Trump is running against a generic white guy the elite political media mostly likes rather than a woman it mostly despises, which means that even when Barr tries an October surprise it’s unlikely to go anywhere. The Comey letter had the impact it did because it landed in the context of more than a year of stories implying that there was something about Hillary Clinton and EMAILS that proved she was more untrustworthy and corrupt than the career con artist she was running against.
Nothing is certain, but Biden is in fact a strong favorite. And if the United States had a remotely democratic process for selecting the president there would be no doubt whatsoever.