Republican presidential candidate Ted Cruz on May 2 tried unsuccessfully to win over a small crowd of supporters of his chief rival, front-runner Donald Trump, at an impromptu campaign stop in Marion, Ind. (Reuters)

Republican presidential candidate Ted Cruz on May 2 tried unsuccessfully to win over a small crowd of supporters of his chief rival, front-runner Donald Trump, at an impromptu campaign stop in Marion, Ind. (Reuters)

Carly, we hardly knew ye.

A week ago, Carly Fiorina was in a good position to enjoy the sheen of respectability she had acquired. The former Hewlett-Packard chief had run a solid presidential campaign and established herself as an adroit debater who could cut Donald Trump down to size.

Then, on Wednesday, she became Ted Cruz’s vice-presidential “nominee” — accepting a nomination Cruz had no authority to bestow. In a case of exceptionally bad timing, Fiorina hitched herself to Cruz at precisely the moment his candidacy began to implode, as polls showed him fading in must-win Indiana before Tuesday’s vote. Fiorina’s previous criticism of Cruz and her checkered record at HP were again in the news. And now, alas, so is her singing:

I know two girls that I just adore

I’m so happy I can see them more

Because we travel on the bus all day

We get to play, we get to play

Fiorina sang these words to Cruz’s two daughters in her “acceptance” speech. The eerie crooning, of the type heard in horror movies before something bad happens, made Fiorina a late-night sensation. “It’s like Disney gave the wicked stepmother her own song,” Stephen Colbert observed.

Musical sleuths identified the melody as Irving Berlin’s show tune “You’re Just in Love”:

Put your head on my shoulder

You need someone who’s older

A rubdown with a velvet glove

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There is nothing you can take

To relieve that pleasant ache

You’re not sick

You’re just in love

This selection by Fiorina — she delivered the unsettling news that she has four verses to her song — puts the “old” in Grand Old Party. It’s from the 1950 musical “Call Me Madam,” in which the Ethel Merman character, an heiress and ambassador, comforts her young aid, a diplomat in love with a princess.

Fiorina, 61, is the one taking orders from Cruz, 45, but their relationship is no less peculiar.

It’s not Fiorina’s fault that news broke just after her “nomination” was announced that former House speaker John Boehner, still a popular figure in nearby Ohio, had called Cruz “Lucifer in the flesh” and a “miserable son of a bitch.” Nor was it Fiorina’s fault that Indiana Gov. Mike Pence on Friday gave Cruz such a tepid endorsement — he said that he “will be voting for Ted Cruz” but that “I particularly want to commend Donald Trump” — that Pence attempted a do-over in the form of an op-ed in the Indianapolis Star.

But if Fiorina picked investments the way she picked her candidate, you can see why HP stopped requiring her services. She bought Cruz at the peak, when polls showed him close in Indiana. But an NBC-Wall Street Journal poll Sunday found Trump up 15 points.

And now Cruz and Fiorina have to explain all those things she used to say about him: that “Cruz is just like any other politician”; that “there’s no honor in charging a hill that you know you can’t take, only casualties, although Ted Cruz maybe got name recognition and money”; and that it was “odd that Senator Ted Cruz did not renounce his dual Canadian citizenship until 2014.”

Cruz now also has to defend Fiorina’s record at HP, where she let go thousands and sent jobs to India and China. “Will the Cruz-Fiorina team do the same thing to Indiana that she did to Hewlett-Packard?” Fox News’s Chris Wallace asked Cruz on Sunday.

The treatment didn’t improve for Cruz when he took questions from reporters Monday morning in Indiana: How can he possibly beat Trump in California? Is there a path to victory if he doesn’t win in Indiana? Would he drop out of the race before the convention in July?

“I am competing to the end,” said Cruz, reminding all of his endorsement from Pence — and his running mate. “I am so proud this week to be standing shoulder to shoulder with my vice-presidential nominee, Carly Fiorina.”

But Fiorina was not standing at his shoulder later Monday, when he waded bravely into a group of Trump supporters outside his event. Cruz bravely tried to engage them in calm discussion. “Donald Trump is deceiving you. He is playing you for a chump,” Cruz said.

The Trump supporters taunted Cruz: “Do the math. . . . Time to drop out. . . . You are the problem, politician. . . . Where’s your Goldman Sachs jacket? . . . Lyin’ like you always do. . . . Are you Canadian?” America, one said, would be a better country “without you.”

If Cruz hadn’t established himself as a singularly unlikable candidate, one could almost have felt sorry for him in that moment. He needed urgently for Fiorina to sing more Ethel Merman:

They think that we’re through, but baby,

You’ll be swell! You’ll be great!

Gonna have the whole world on the plate!

Starting here, starting now,

Honey, everything’s coming up roses!

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