The Harris - Walz phenomenon is a desire for a return to normalcy. Folks are sick and tired of Dystopia Donald messaging, his firehose of lies, and bizarre bluster, and attacks on our democratic republic - including J6.
2016 was a fluke - HIllary's campaign was ill thought out (even though she still won the popular vote). They sought a mandate instead of protecting the Blue Wall. The MSM wanted Trump and insisted he'd act Presidential any day now. We're still waiting! Hillary had an incredibly high negative Q - she wasn't likable. Then there was the Comey letter...which was a bust, but early voting and momentum swung toward Trump. Trump only ran to increase his brand which had been failing at business venture after business venture.
Walz and Kamala are more like regular people who will work with the people and for the people. I don't agree with all of their policies, but I don't think this election is about policy. It's about climate.