There are a couple of polls showing Biden in the lead now in a 5-way race, but most still have Trump ahead. These polls sowing Biden "surging" have typically been outliers, likely so the media will have something sensational to report, and those polls have been flipping back after a couple of weeks. And, most of them have been conducted by the media themselves or colleges, not professional polling agencies. So I wouldn't put much stock in any single poll. This is why I usually post poll averages.
Just remember...Trump lost the popular vote to Hillary by 2.1%, yet still won in the electoral college. The numbers there still show Trump winning easily. He is still leading in every single battleground state, and is very close to flipping two "blue" states.
Beyond that...there are several dynamics that are hard to predict. Just how much has Trump actually gained among blacks and Hispanics? Some of the polls show significant gains, but it's hard to gauge. I've read that it's harder to get accurate polling from minorities.
Then there's the question of turnout. There's good indication that some of Biden's voters won't go to the polls because they aren't happy with him. But will the same happen to Trump because of the conviction? No one really knows about either of these.
Will mail-in voting be abused again? I wish I was more confident that it's been fixed, but I'm not.
And, of course, the question of whether or not they will replace Biden. I'm still leaning that they won't, but it could happen. Gonna be seriously interesting if they do, though.