Here, then, in eastern Iowa and in concentrated form, was a preview of what is to come in the about-to-be-announced presidential candidacy of DeSantis — not just his run but also the often stage-dominating prominence of her role.

For some time now she’s been seen mostly and by many as an absolute superstar of a political spouse, a not so “secret weapon,” even something like his saving grace — an antidote for her sometimes awkward husband, social in a way that he is not, charismatic in a way that he is not, generally and seemingly at ease in the spotlight in a way that he so often and so evidently is not. A telegenic former television personality, a breast cancer survivor and a mother of three young kids, Casey, 42, has a sort of policy portfolio of her own that ranges from hurricane recovery to issues of mental health. In the DeSantis political project, she is unusually important and uncommonly involved, according to hundreds of interviews over the last few years and more than 60 more over the last few weeks — an array of former staffers, current supporters and donors, state and federal lawmakers and Florida lobbyists and political professionals. “She is every bit as involved in Ron’s rise as Ron is himself,” David Jolly, the ex-GOP Florida congressperson who’s now an MSNBC analyst, told me. “In shaping him, in driving him … it’s different,” said a veteran Republican lobbyist. “Unlike any first lady in my extended memory,” added Tallahassee fixture Mac Stipanovich.

For nearly as long, too, though, others who have worked with her or around her have nodded more quietly to the downsides of the starring part that she plays. She is and always has been by far his most important adviser, they say, because she is hesitant to cede that space to nearly anybody else. The DeSantis inner circle is too small and remains so, they say, not only because he constitutionally doesn’t trust people but because she doesn’t either. Especially forthright are the people who are granted anonymity on account of their fear of retribution given their power — not just his but hers. “She’s the power behind the throne,” a Republican lobbyist told me. “The tip of the spear,” said a Republican consultant. She is, they say, in the middle of good decisions of his, but bad ones, too. One in particular during the first year of his administration struck many then as a shortsighted miscalculation and looks to them now like a possibly fatal mistake — the ouster of Susie Wiles, the well-respected operative who had helped former President Donald Trump win Florida in 2016, and then helped DeSantis, 44, get elected governor in 2018 but now is running Donald Trump’s rival White House bid.

“Have you ever noticed,” Roger Stone, the notorious political mischief-maker who is both a DeSantis antagonist and a many-decades-long Trump loyalist, remarked in a Telegram post last fall, “how much Ron DeSantis’ wife Casey is like Lady Macbeth?” — an agent, in other words, of her husband’s undoing.

Stone’s hyperbolic charge is but a piece of a broader effort on the part of Trump forces to kill in the crib the candidacy they consider their greatest threat. They recently have scored a series of key albeit early strategic wins — a flurry of in-state endorsements, for instance, contributing to the perception of a novice, faltering DeSantis that’s also visible in a slide in early primary polls.

In the tragic drama, of course, Lady Macbeth prods her husband to kill the king so she can be the queen. At this juncture, the literary analogy goes only so far. Ron DeSantis has trouble even criticizing Trump by name, but with the head-to-head battle about to begin, the role of his wife is of paramount concern to many in and around the world of DeSantis, as well as those considering whether to back him. The more complicated but also more instructive reality is that she is neither the fawning caricature she’s made out to be in conservative and even at times mainstream media nor a Shakespearean villain. She might well be a bit of both, say even some DeSantis proponents, and somewhere in this tension sits the central dynamic of the pending DeSantis campaign. She can ameliorate some of the effects of his idiosyncrasies. She can also accentuate, even exacerbate, his hubris, and his paranoia, and his vaulting ambition — because those are all traits that they share. He wouldn’t be where he is without her. He might not get to where he wants to go because of her.

“He’s a leader who makes political decisions with the assistance of his wife, who was elected by nobody, who’s blindly ambitious,” said a former DeSantis administration staffer. “And she sees ghosts in every corner.”

“She’s more paranoid than he is,” said a second staffer.

“He’s a vindictive motherfucker. She’s twice that,” said a higher-up on one of his campaigns. “She’s the scorekeeper.”