Presidential candidates were obliged to pretend yesterday that they would rather spend Christmas exchanging gifts with their families than trading insults with each other in the freezing electoral battlefields of Iowa and New Hampshire.

Their irritation at missing a full day’s campaigning so close to the Iowa caucuses on January 3 has been compounded by having to pull their hardest punches and soften negative tactics for fear of being seen as a Grinch, a Scrooge, or — even worse — someone desperate to get elected.

At this stage momentum — or “The Big Mo”, as George Bush Sr once put it — is everything. So for those who don’t get a vote in the caucuses, the primaries, or even in the presidential elections, The Times is offering a chance to be your very own candidate by playing Momentum.

Cut out your chosen candidate as a counter and get down into the mixture of high ambition and low blows that is a primary campaign — taking for your guide the Republican candidate Mitt Romney. He did his best to be festive by holding a carol service with supporters on Monday but could not resist launching one more assault on the tax policies of John McCain, who is fast closing on him in New Hampshire. Mr McCain’s campaign had an easy response: “Give it a rest,” it told Mr Romney. “It’s Christmas.”

Hillary Clinton was, like others, running a Christmas TV advertisement. She was shown wrapping up presents and sticking on labels such as “universal healthcare” and “alternative energy”. Critics said it reminded them how, even at this time of year, all she cares about is public policy.

Her fellow Democrat Chris Dodd is a desperate man, barely registering in the polls despite campaigning relentlessly for the past year. He has now moved his entire family to Iowa and promised to buy only Iowan-made (and apparently antique) presents for his long-suffering children. They posted a sign outside their home in Connecticut reminding Santa Claus of their temporary address. Yesterday he promised to go ice skating with aides and serve them hot chocolate.

Most of the 15 candidates still running for the presidency hope to use Iowa, which is holding its caucuses earlier than ever before, as a springboard for the New Hampshire primary on January 8. The combination of these two elections have, for more than 30 years, set the tempo for the nomination process elsewhere in America.

Although Mrs Clinton is way ahead in national opinion polls for the Democratic nomination, she is in a tight three-way fight with John Edwards and Barack Obama in Iowa. Mr Obama, who is neck-and-neck with her in New Hampshire and South Carolina, believes he is building momentum at just the right moment to overtake her.

Rudy Giuliani, who is losing momentum in the Republican race at just the wrong time, is now concentrating on later and larger states, having, in effect, conceded defeat in the first two contests. He spent Christmas Eve reading ‘Twas the Night Before Christmas to needy children in Harlem, New York, and assuring reporters that despite his health scare last week he was “cancer-free”.

Today he is scheduled to appear in Florida. One of his Republican rivals, Mike Huckabee, will also be in the Sunshine State, hosting a fundraiser as he tries to build the finances and organisation to match his soaring opinion poll rating.

Mr Romney and Mr Edwards have a series of campaign stops in New Hampshire, some scheduled so early that they will take place before many voters have got out of bed.

Mrs Clinton and Mr McCain, as well as Joe Biden for the Democrats and Fred Thompson for the Republicans, are scheduled to speak in Iowa. All hope for a spurt of momentum and fear a sudden loss. But anyone trying to work out how to play the game should look no further than Bill Clinton who experienced both 16 years ago. He was expected to win New Hampshire easily but was hit by claims that he had slept with Gennifer Flowers, a former nightclub singer, that he had dodged the Vietnam draft and smoked cannabis at Oxford.

He denied all charges with varying degrees of credibility but slumped 20 points in the polls before a masterful performance in a television interview in which he held hands with Hillary and they professed everlasting love. He ended up coming second in New Hampshire and went on to win the nomination as the “Comeback Kid”.

Pick up that Momentum and you’re on your way.

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