Sweeney would win, and he would have the backing of the Democratic machine. I'd imagine Sweeney entering scares off any serious Republicans.
Don't you think Republicans would be ripe to win back the governorship in 2025? Yes, NJ is a blue state, but it elects Republicans.
I think Trumpism has killed any chance of a Republican being elected statewide for a while...
I think the antipathy towards Trump will start to fade when he leaves office. If he loses, he'll continue to tweet and criticize Biden from the sidelines, but he won't really be taken seriously anymore, since a lot of elected Republicans personally hate him, which they would only do so even more if he costs them the presidency and Senate. He'll just be seen as a crazy old man, like Grampa Simpson yelling at a cloud.