This is another question that needs more specificity in order to have much meaning. Who will endorse him in the primary as of *when*? I’m sure that if he runs and wins the nomination, then most Republican politicians will have endorsed him at some point by the time he clinches the nomination. But in many cases, it’ll only happen at the last minute. Because there are a ton of Republicans in Congress who seem to not want to talk about Trump, and try to dodge the question when asked about him. Even Ron Johnson in 2019 wouldn’t talk about whether he was going to support Trump for re-nomination, and that was when he was the sitting president, a situation in which most members of a major party pretty much automatically back the sitting president of their party for a another run:
https://thehill.com/homenews/senate/427973-endorsing-trump-isnt-the-easiest-decision-for-some-republicansAnd the thing is, Trump seems to not really care. If you criticism him, then he holds it against you. But if you just dodge on the question of whether you support him, he doesn’t seem to notice.
So I’d expect that if he announces another presidential campaign, that he’d get some endorsements right away, but a large fraction of congressional Republicans would just hold off endorsing anyone, and wait and see what happens. Many still won’t have endorsed anyone at the time the primary voting starts, but then would finally endorse Trump either just before or just after he formally clinches the nomination.
