Alaska is the only race he endorsed a challenger to an incumbent.
The others are open seats or held by Democrats.
True, and they do not have the incumbent advantage, so they’re head up against whomever the demscum run, both sides are challengers for the open seat. Dooh. None of the candidates you listed whom are incumbents are likely to lose because they have incumbent advantage and the people in their state like them, they were losing battles. That’s the point.
You’re counting on the voting process being legit. I’m not wearing rose colored glasses in that regard.