I have to admit: I have no idea how Republicans are going to react to Donald Trump’s latest scam.
Trump’s ability to move votes in Republican primaries is limited and has been over the years. His endorsements are most valuable in multi-candidate fields in which there’s no obvious leader, since in that type of election voters are typically looking for cues to decide how to vote. But he’s rarely demonstrated much of an ability to affect more stable contests. Earlier this month in the Texas primaries, Trump-backed candidates seemed to do no better than they would have without his endorsement.
That said, at times Trump has shown a pretty good ability to jump to the front of the parade — endorsing the candidate otherwise most likely to win, and then taking credit when it happens. That’s pretty much what he did in Texas, where he endorsed incumbents and shied away from elections that were harder to handicap. There’s nothing wrong with that; convincing other Republicans that his endorsement is valuable by using it selectively is a pretty normal political gambit.