New York Times.

Tuesday’s primaries in Pennsylvania, Connecticut, Maryland, Delaware and Rhode Island could bring Donald Trump close to securing the delegates he needs to win the Republican presidential nomination, though probably not all the way there. After a series of missteps, he seems to realize that he needs to improve the style and substance of his campaign among both Republicans who resist him and the electorate at large.

That’s why Mr. Trump has hired a Henry Higgins to work on his comportment. Paul Manafort, Mr. Trump’s new campaign chief and an old-guard Republican strategist, has eclipsed the abrasive Corey Lewandowski and his nonnegotiable “Let Trump Be Trump” approach. Mr. Manafort’s ambition is to turn this Eliza Doolittle into a candidate more acceptable to decent society, in time for the general election.

Mr. Manafort rolled out his Pygmalion project with a PowerPoint presentation behind closed doors at the Republican National Committee retreat in Florida last week. “The part he’s been playing is evolving,” Mr. Manafort assured the Republicans. Mr. Trump doesn’t really mean it when he says things like he’ll deport 11 million immigrants, or block Muslims from entering the country, or kill terrorists’ children, or when he maligns women. He’s doing all that, Mr. Manafort suggested, to win the primaries; come the general election, Mr. Trump will bloom into his truer (and presumably kinder and gentler) self.

Mr. Trump himself has been saying the same thing in private for months, including in regular calls to members of Congress and Republican leaders.

“He’s always said privately that he’s learned from negotiations that you start from the far end. If you start in the middle you lose,” says a longtime Republican operative who was in the room in Florida. “When he said those things, he was stimulating the group of voters that he capitalized on. Can he pivot to bring in more voters so he has a larger base in the general election? Most people think he can. But is there enough time?”

Starting small, the Trump-improvement strategists have already persuaded Mr. Trump to deliver a New York victory speech devoid of epithets and to stop calling the Sunday morning TV shows to bloviate on this or that. Mr. Trump followed up his New York speech with a couple of soft-focus interviews, telling one reporter that he would be “more disciplined,” and use a teleprompter like a proper politician.

But Mr. Trump has reverted to bad habits. He’s still telling lies, and earned four Pinocchios last week for saying that ISIS is “making a fortune” on Libyan oil the terrorist group doesn’t control. On the trail last week, he showed crowds that he hasn’t forgotten or doesn’t regret what he said about Mexicans and Muslims. “I sort of don’t like toning it down,” he said in Connecticut. “Isn’t it nice that I’m not one of these teleprompter guys?”

Mr. Trump knows that to do well in Tuesday’s primaries he still needs those “motivated voters” who want him to say what other politicians won’t. Yet the Trump on the stump is the true man. However copiously applied, cosmetics cannot obscure his brutish agenda, nor the narcissism, capriciousness and most of all, the inexperience paired with intellectual laziness that would make him a disastrous president.

Come Wednesday, with Tuesday’s primaries safely out of the way, Mr. Manafort’s makeover efforts will enter a new dimension — Mr. Trump’s first foreign policy address. The campaign promises no less than “a clear, consistent long-term foreign policy for making America safe and prosperous.” That’s sure to be an interesting test, given that until now Mr. Trump has demonstrated limited knowledge of foreign trade policy, Middle East issues or geography. A sometime adviser, Roger Stone, saidin an interview released Monday that the presidency “is show business” to Mr. Trump, who Mr. Stone said lacks the bandwidth to read a 40-page briefing book.

Whatever persona or good manners Mr. Trump chooses to display from now on, he can’t hide his unfitness for the presidency.