I don't understand the "Democrats staying at home during Thanksgiving" argument, like whether being at home or not during a holiday is a partisan issue?
Previous studies have shown that if election day were not a Tuesday, but a Sunday or holiday - turnout and the Dem vote would increase because more Democrats and Blaxicasians would have the chance to vote.
I assume this is also the case for polling and holidays, because many ordinary working class folks (= minorities, Democrats) are at home and picking up the phones during these days. But not during the work week. Republicans, who are generally more wealthy and more flexible when it comes from being at home and working from home, are more likely to respond to pollsters during the work week.