I agree DeSantis vs Newsome seems like the most likely matchup.
If Trump runs again, I think only DeSantis lines up against him, and I'd give DeSantis the edge in that two way race. But if Trump doesn't run again, that's where we'll see a few other Republicans come out, and in a crowded field, it may go to someone who's a better showman than DeSantis, but I haven't seen enough of others to say who has that quality.

On the Democrats' side, Kamala will run if Biden chooses to endorse her. It is more likely that Biden will endorse no one. In that case, Kamala won't run, or, if she does run, she won't last long. That leaves Boot-Edge-Edge and Newsome. Perhaps there is another governor who tries. I doubt any Senator or Rep tries.

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