Even if you believe the Marist poll, it's not good for Biden. As best as I can tell it's a national poll. For Biden to win he would have to be up at least 4 points in a national poll based on past correlations of national polls and winning campaigns. Article in today's NY Times (admittedly not the most objective source) has interviews with Arab-American voters in Michigan who will not vote for Biden. If Biden loses Michigan, he must win PA, WI and at least one of NV or AZ. It's possible but a very steep hill to climb.