Supporters of President Obama are not sure what to be more vexed by this week.

The fact that the man they had worked so hard to get re-elected to the White House put in a cavalier debate performance, reeking of “droit de seigneur” in front of 67 million Americans. Or that Mitt Romney is getting away with a sudden reversal on so many issues it has given most of us whiplash.

The polls are alarming for the Obama camp. Although this election was never a done deal for the president, he had been leading Romney, especially in those all important swing states.

After three weeks of Mittmouth and a Republican Convention that had all the euphoria of a board meeting, Obama’s lead was growing daily. In golfing terms, he was finishing his round on the 18th green, well under par and well ahead. All he needed to do was land two good putts and the trophy was his.

09 romneyobama r w Obama camps alarm as the Romney robot springs to life

Instead he took his wedge and dug up the green, as if he was looking for oil or truffles or may be Golden Tablets. Despite all their bravado, the polls have made the Obama campaign people blanch.

In one, out today, Mitt is leading the president – albeit by a wafer-thin margin- for the first time in all 11 swing states, including Ohio. In another, Obama’s legendary support amongst women has collapsed. His numbers on economic management are worse than ever and Mitt, the “one percenter’s one percenter”, has suddenly on par with Obama in terms of caring for the American people.

Mitt Romney has gone from arch-capitalist inflictor of pain to feeler of pain. American politics is littered with candidates who put in a great first debate performance and then tank. But rarely, if ever, has there been such a swing after the debate, with the exception of Jimmy Carter versus Ronald Reagan in 1980 – and we all know how that ended for the incumbent.

So how can one debate performance make such a difference and can it last? Here’s what I think. Forget for a moment that Romney is a weather vane. In statistical/historical terms this should always have been his election to lose, because of the state of the economy, the belief amongst a majority of Americans that the country is heading in the wrong direction and Obama’s consistent job rating since 2010 below 50 per cent.

But helped by the circus of the Republican primaries, which was a treasure trove of voter-tested attack lines against Romney and by Mitt’s own incompetence, the Obama campaign turned what would have been a referendum on a stalled presidency into a referendum on an impossible candidate.

They defined Mitt early and viciously. He became the Velcro candidate, as opposed to the Teflon. Everything they threw at him stuck. Republicans were frustrated that his supposedly brilliant CV jarred so horribly with his campaign performance. In other words expectations had been convincingly lowered by just about everyone including the candidate himself.

There is nothing like a surprise in a race that seems to be stuck in a groove. And last week Mitt Romney delivered one in his passion, sharpness and language that most Americans just had not expected. The Democrats have worked hard to expose Romney’s glaring flip-flops since then, and I have no doubt that the president will be more awake at the next debate.

You probably won’t find him rehearsing with the somnambulant John Kerry in a golf resort this time. And yes, the expectations are now loaded in favour of Mitt Romney. The Democrats have a formidable electoral machine and last month alone Obama raised a staggering 180 million dollars, twice the cost of an entire UK general election campaign.

And yet the fundamental truth of this election has not changed. A slim majority of US voters have long been prepared to contemplate divorce from the incumbent. They just haven’t found a partner to elope with. Since last week they have been looking at Mitt with new eyes. They have been flirting with a robot who has sprung to life and displayed unmistakeable traces of humanity. It’s going to get very interesting.

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