Republican presidential nominee Donald Trump is overhauling his struggling campaign amid sliding poll numbers. (Reuters)

In  case you had any doubt, Donald Trump sent an unmistakable sign that he has no intention of running a legitimate campaign. He demoted his much-maligned campaign chairman, Paul Manafort, and elevated pollster Kellyanne Conway and — no, seriously — Stephen Bannon, Trump pal and chairman of the much-mocked Trump-cheerleading outlet Breitbart News. Neither one has ever run something remotely as complex as a presidential campaign. Bannon is in some sense Trump’s twin — a brawler, a bully and someone unburdened by facts. If you thought the current campaign was a three-ring circus, get ready for a caravan of contortionists, clowns and high-wire walkers.

“I am who I am. It’s me,” Donald Trump said on a Wisconsin talk radio interview on Tuesday. He continued: “I don’t wanna change. Everybody talks about, ‘Oh well, you’re gonna pivot, you’re gonna’ — I don’t wanna pivot. I mean, you have to be you. If you start pivoting, you’re not being honest with people.”

Listen, Republicans. He could not be more clear. There will be no professional campaign. There is no sticking to script. There will be no presidential tone. There will be no end to the conspiracy theories, to the infatuation with Russian President Vladimir Putin or to the lies about what his positions used to be (e.g. his initial stance on the Iraq War). Republicans can no long mollify themselves or remain in the good favor of Trumpkins by waiting for Trump to become something he is not.

Sen. Mitch McConnell (R-Ky.) has told him endless times to use a teleprompter. He does, but then reverts to free association in interviews and speeches.

Republicans have told him to stop spending time in blue states like Connecticut. He won’t.

Republicans have told him to release his tax returns and force his Russia-connected advisers to reveal their financial ties. He won’t.

Hugh Hewitt has lamely asked that he name a cabinet. He not only won’t do that, but he also wouldn’t stick to that lineup (or get any responsible people) any more than he stuck to his judges list. (You recall he immediately started to backpedal when asked whether he’d choose Supreme Court justices off the list.)

Ivanka Trump, supposedly the brains of the operations, is on vacation — with liberal billionaire (a real one!) David Geffen — while her father melts down. Maybe Republicans should take a hint from her holiday from the horror show and Trump’s own pronouncement. Any notion that the Trump adult children could steady their father evaporated with his latest campaign shake-up.

Several things should follow from Republicans’ rendezvous with reality.

First, stop giving advice. He’s not taking it, and recommending that Trump stop being Trump is making Republicans look daft. It creates the false impression that his faults are fixable. Trump’s idea of hiring the “best” people amounts to erratically hiring and firing one set of unqualified advisers after another, none with the skill set to run a presidential campaign.

Second, he’s not trying to improve or run a new and improved campaign. He wants to do it his way, irrespective of whether he goes down in flames. He has already moved on to excusing his loss (e.g. the media are so mean) and pondering a “long vacation.” Republicans at this point should feel free to treat the campaign as a lost cause. The Republican National Committee is truly daft if it continues to fund an unprofessional, chaotic campaign. Endorsements and party support should go to nominees who in good faith are trying to do everything possible to win. You don’t have to believe Trump engages in self-sabotage to see that he is not doing that.

Third, forget the idea that he is going to pull a rabbit out of the hat in the debates. It’s not clear that he will show up, and if he does, he seems willing to do so without rigorous preparation. (Both the campaign and Roger Ailes deny that the disgraced former head of Fox  News is assisting him.) Frankly, he might want to make some excuse not to attend. After all, Trump will have to talk for a full two minutes per question. There will be no cast of Republicans to hide behind. The moderator is not going to be Sean Hannity; he or she will be a serious news person unwilling to let him evade the question or attack the questioner. Even worse, in a town hall setting he’ll have to be polite and respond to real voters. In other words, in all likelihood it’ll be a big stage with a huge audience for Trump to demonstrate just how unpresidential he is. (Remember, he’s not changing.)

Republicans have deluded themselves long enough. He’s not stable, coherent or knowledgeable. The man who never apologizes and thinks he has run a perfect campaign will not shift gears. If anything, he is doubling and tripling down. If Republicans cannot declare him ready right now to govern and recommend Trump as he is right now — not after being sprinkled with presidential pixie dust — they should leave him to his own devices and get on with the business of trying to save the House and Senate majorities.