There were clues - and we missed them.
That Mitt Romney would turn in a polished debate performance was no surprise. He spent a lot of time preparing for his meeting with President Barack Obama in Denver, Colorado.
There were long "debate camps".
He was battle hardened from the 19 televised Republican debates, and when under pressure in those, he performed.
What we should have expected, and didn't, was that he would tack so clearly to the political centre to court the independents and undecided voters who may yet tip this election.
Romney governed as a moderate while in charge in heavily Democrat Massachusetts. But keen to pursue a presidential bid, he spent his final months in the state house in Boston and the subsequent six years running for president describing himself as "severely conservative".
It was enough to secure him the Republican nomination, although there were many in the party who doubted. They only felt comfortable when he selected Paul Ryan as his running mate a budget-slashing Tea Party favourite.
As the Republican campaign wound up, when one of Romney's most trusted advisers, Eric Fehrnstrom, was asked if the candidate's rightwing positions on social issues and government programmes would hurt him in the general election.
Etch a Sketch label
Fehrnstrom likened the campaign to a child's toy, the Etch a Sketch, saying: "You can kind of shake it up and we start all over again."
Romney and Fehrnstrom were attacked by Democrats and Republicans, saying the candidate was a flip-flopper, happy to change his message rather than carry a level of consistency through the campaign.
Then there was the former governor's dismissive comments recorded at a high price fund-raiser in May.
He told the audience 47 per cent of Americans would never vote for him because they were "victims", dependent on government handouts.
Initially he claimed he'd simply spoken inelegantly. Then, just before the first debate in Denver, he said he, in fact, was wrong, and should never had said such a thing.
There was also the frequent references to Ronald Reagan's presidential debate performance - and how he swept past Jimmy Carter in 1980, despite being several points down.
In fact, Reagan was ahead in the polls by the time the debate came around, just a week before the election.
Reagan was regarded as a frightening figure from the right before the debate, but presented himself as a genial man of the centre.
That was enough to swing many independents and wavering Democrats behind him.
The clues were all there. The move to the centre is a calculated gamble for Romney.
In an election where the Republicans feel an almost visceral dislike of the president, he is hoping the party will forgive him a few shifts to the centre as long as he keeps hammering the "cut spending, cut taxes mantra".
Portraying himself as a practical centrist willing to work across party lines to get things done, may get enough independent voters on his side to swing key states, and so the election. It will also give him some room after the election, if he is successful, to claim to the rightwing of his party that he was elected as a moderate Republican.
Romney needs another good debate here in New York to show that his performance in Denver was not simply a one-off and to build on the momentum that he has given his campaign.
He has closed the gap - and in some cases overtaken - Obama in many battleground states.
He has excited the party about his candidacy in the way he failed to do for so long.
Another loss for Obama and there might not be time to recover the damage before the last debate and the election itself.
Only Mitt Romney knows if he is truly a conservative or a centrist. But he is clearly a pragmatist.