Reports of its death may yet prove exaggerated, but stand by for an avalanche of obituaries for the captivating political career of Donald J Trump. The cascade is scheduled to begin in the early hours (GMT) of Wednesday.

If he loses Tuesday’s primary in Wisconsin to Ted Cruz (or The Even More Repulsive Ted Cruz, to give the Texan his full official title) – the damage to Trump’s hopes of leading the free world might be terminal. His chances of collecting the 50 per cent of Republican delegates needed to secure automatic nomination at July’s GOP convention will recede – and if he isn’t nominated automatically, he will surely not be nominated at all.

But how has it come to this? A fortnight ago, the tangerine huckster and his trusty running mate, That Thing On His Head, appeared to have the nomination in the bag with the betting markets making him a 75 per cent virtual dead cert.

He was still saying staggeringly stupid and/or distasteful things on the hour every hour, it being a medical impossibility for his larynx to vibrate without an imbecility drifting from his gob. Yet the received wisdom, which six months ago read him the last rites every time he said something crazy or vicious or both, had reversed. It now held that he could say nothing – literally nothing; not a recitation from Mein Kampf, nor a confession to being a serial killer; naaahh-thing – to deter that relatively small but disproportionately noisy demographic of barely disguised racist filth known for short as “the Republican base”.

And then, miraculously, the high priest of strutting bombast found the silver suicide bullet. In another context (though God knows which), you could sympathise. After emerging unharmed from all the forays into misogyny – sourcing a Fox News anchor’s interrogatory style to her menstrual cycle; describing Hillary Clinton as “disgusting” for going to the loo, etc – how could his contempt for women bring him down?

Yet it threatens to do just that. His charming observation that a woman should, in some undefined way, be “punished” for having an abortion was the step too far which had come to seem as mythical a beast as the unicorn. Even hellfire evangelical Republicans who would outlaw abortion in cases of rape couldn’t stomach that. To them, a woman who terminates a pregnancy is a sinner to be brought to repentance; but (unlike the doctor who performs it) absolutely not a criminal.

Trump quickly recanted, but too late. From that moment, his odds began to lengthen, and the betting exchanges now reckon him about as likely to lose the nomination as win it. According to the electoral mathematics, this flatters him. If he loses Wisconsin, as seems certain, it will be extremely hard for Trump to bag half the delegates.

In which case, ladies and gentlemen, stand by for an open convention – one of the rarest and most entertaining spectacles democratic politics anywhere on this accursed planet can offer. If no one has won a majority before it starts, delegates are released from their duty to vote according to primary and caucus results after the first, indecisive ballot. Thenceforth, they are not obliged to vote for an existing candidate. They can vote for anyone they choose.

There hasn’t been an open convention in real life for decades, but for a useful fictional guide I recommend the latest series of House of Cards. No spoilers here. Suffice it to report that it concerns the selection of Frank Underwood’s vice presidential running mate, and gives a flavour of the riotous backstage horse-trading to be expected in July should Trump arrive short of the 1237 delegates he needs.

Given how despised and friendless he is, Ted Cruz is not expected to be the beneficiary. The other current contender, Ohio governor John Kasich, who in this field passes for a moderate, might have a shot. Mitt Romney may show up hoping to parlay his crushing defeat last time into another crack at the White House, although his 2012 running mate Paul Ryan, the wonkishly inoffensive Speaker of the House, is seen as the probable establishment pick. But after four, five, six or seven ballots, it could be anyone over 35 with a passport and a pulse who emerges.

Whoever is eventually chosen, Hillary Clinton will be wearing the most beatific grin as the mayhem unfolds. In the event of Trump wining a plurality but not a majority of delegates, and then being denied the nomination, millions of his fans – screeching, self-pitying dimwits who need no provocation to whine about being cheated – will go berserk with rage, and refuse to vote in November for the Republican candidate.

So if the game truly is up for The Donald, the gift of consolation comes wrapped in a richly ironic bow. After spitting so much misogynestic poison, the political achievement for which his name may echo through history is ensuring that an occupant of the Oval Office is addressed, for the first time, as Madam President.

•Sourced from The Independent of London. Photo shows Donald Trump.

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