Iowa caucus: Marco Rubio’s unexpectedly strong showing is the most significant result

Another strong performance in New Hampshire, and a three-horse race with Ted Cruz and Donald Trump beckons

Republican presidential candidate Marco Rubio acknowledges the audience at a caucus night celebration in Des Moines, Iowa (AP)

To use the vogue-ish terminology of Star Wars, the empires struck back in Iowa – or rather the establishments of the Republican and Democratic parties, shaken to their foundations by the insurgent candidacies of Donald Trump and Ted Cruz in the case of the former, and by Bernie Sanders in the case of the latter.

Iowa gets as many elections wrong as right. It provided launch pads for Jimmy Carter in 1976, for George W Bush in 2000 and for Barack Obama eight years ago. But Ronald Reagan lost there in 1980, and despite his victory on Monday it’s as hard now to see Mr Cruz winning it all in November as it was before the vote.

At first glance the Democratic establishment doesn’t appear to have had a great night. Did not Mr Sanders, self-professed socialist and merest afterthought just six months ago, come within an ace of defeating the mighty Hillary Clinton machine?

Indeed – and there’s a strong possibility he will win New Hampshire by a resounding margin next week. Mr Sanders is from neighbouring Vermont, and he’s just the sort of plain-speaking iconoclast who does well in the nation’s first primary (see Eugene McCarthy in 1968, Pat Buchanan in 1996, and John McCain in 2000 and 2008).

But a win is a win. Ms Clinton seemed to have eked out the narrowest of victories – but that’s far better than the third place she managed in Iowa eight years ago. When the campaign goes truly national next month, her organisation and appeal to minority voters should see her through.

Her biggest danger may not be Mr Sanders, but the risk of indictment over her use of a private email server when Secretary of State.

For the Republican establishment, however, Iowa is cause for unequivocal celebration.

Yes, the loathed Mr Cruz won, but Donald Trump, its other source of nightmares, was nearly beaten into third place by Marco Rubio, who looks like bearing the more moderate conservative standard into the crucial contests ahead.

By far and away the most important result in Iowa was Mr Rubio’s unexpectedly strong finish. For weeks senior Republicans have been pleading for a winnowing of the field, whereby a single Establishment challenger emerges to take on Trump/Cruz. Iowa has got the winnowing started. New Hampshire may complete it.

Mr Rubio won 23 per cent of the caucus vote. Between them his prominent governor and ex-governor rivals – Jeb Bush, Chris Christie and John Kasich – amassed a pitiful 7 per cent. All three have bet the ranch on New Hampshire.

Yes, they’re polling better there than in Iowa. But anything short of a major breakthrough next week, and they will surely be forced to pull out. Ditto the likes of Ron Paul and Carly Fiorina, already irrelevancies.

Mr Rubio’s success gives him a powerful following wind. Another strong performance in New Hampshire, and a three-horse race with Mr Cruz and Mr Trump beckons. All along, the party establishment has felt Mr Rubio is its most electable candidate in November.

Iowa’s voters have now sent a similar message. Republicans may not be such fools after all.

Follow this link for the latest coverage of the Iowa caucus