Trump's campaign believes this. They just dramatically increased their ad spending in Iowa, a state which he won by 10% in 2016, and where the polls show he is tied.
The polls reflect today's reality. If the election were held today, if the polls are accurate, Biden would rout Trump in a landslide, getting close to 400 EVs.
Why do you honestly care? Soon enough some milktoast elitist candidate will come along and take Trumps place and all will be right in your world again