IIRC, in 2016 Santa Clara County, where I live, voted 70%-75% HilLIARy and ~25% Trump (with Stein and that Hate-Trumper getting the remainder). I saw quite a few HilLIARy stickers at the time. Other than the Covid traffic reduction, I have the same commute, and I still don't think I've seen a Biden Sticker. I won't say that California is in play, but while Trump got a fraction under 32% of the vote in 2016, I would not be surprised if he gets between 40% and 45%.
When it comes to bumperstickers and signage, I'm not seeing much enthusiasm for Biden. I don't think the nomination of Kammy will improve that (from a Biden-Harris POV).