And, as other posters have pointed out, Biden did collapse. Terrible performances in IA and NH (which is a good reason to bet Biden won't improve greatly in states like MI or WI). What only saved his campaign was near-universal support among one of the most idiosyncratic American voting blocs (rural, older Black women in the South).
THANK YOU WHITES!
Biden's polling lead vs Trump is stagnant right now because the campaign (and Biden himself) aren't in the news. That won't remain the case into the fall. Just like Iowa and New Hampshire, the more of Joe Biden voters see the less they'll like him.
But voters saw a lot of Joe Biden, on TV that is, for three days before Super Tuesday, and then he went on to massively outperform expectations literally everywhere?
