Polls are deliberately manipulated, and they're used to compel the herd mentality to adhere to pop culture. For example I don't believe the moonbat messiah obozo was all that popular, it was a cult of personality, and the republicrat nominees were almost as bad as hitlary or biden.
Besides that, the burnout from the Bush years of democrooks getting everything they wanted except a surrender to jihad disgusted most voters. Now that we've got a guy who fights treasonous malignant parasitic bed wetting leftist filth, I think the turn out for him will be larger than last time, and the lack of excitement for plugs will drag the rest of the GOP to a serious victory in spite of whatever agitprop liberal apparatchiks publish.