Doug Hoffman does not look much like a rebel who could shape American politics for years to come.

Dressed in blue blazer, khaki trousers and spectacles, he looks more like a beady-eyed accountant — which is exactly what he is. Yet by taking on the Republican Party establishment and running for Congress as a third-party candidate in upstate New York, this political neophyte has become the poster child for Sarah Palin, the former Alaska governor, and the American conservative movement.

“I am fighting for the soul of the Republican Party because I believe my values and ideals represent what the party aspired to represent,” he told The Times at a campaign stop in the toilet-paper manufacturing town of Plattsburgh. “That is why I got in this battle. I am trying to get the Republican Party back on track.”

The by-election — for the House of Representatives seat in the state’s 23rd district — takes place tomorrow, but Mr Hoffman has already won his battle. A poll at the weekend showed him running neck-and-neck with the Democrat, while the official Republican candidate lagged 15 points behind.

Within hours of that poll the official Republican — Dede Scozzafava, a moderate who supports unions, “gay marriage” and abortion rights — abruptly pulled out of the race for a seat that has been held by a Republican since just after the American Civil War.

The national Republican Party had no choice but to throw its weight behind Mr Hoffman — who local party bosses had rejected as a candidate this summer. In a parting shot at her own party, Ms Scozzafava rubbed salt in the wound by endorsing the Democratic candidate, Bill Owens, as an “independent voice”.

Even before this weekend, however, Mr Hoffman had attracted the support of some of the party’s leading lights, including Mrs Palin, the darling of the conservative wing. His campaign is almost certain to pull the Republican Party to the right — answering the question of how it would react to such a comprehensive defeat in last year’s elections.

A drift to the right could make it hard for the Republicans to capture the middle ground in the mid-term Congressional elections next year. A recent Washington Post/ABC News poll found that only 20 per cent of Americans identified themselves as Republican.

Neverthless, that is where the party seems to be heading. “I think the Republican Party and conservatives all across the country are going to have what I call a ‘Come to Jesus’ meeting,” said Mark Barie, the chairman of the Tea Party movement in upstate New York — a group passionately opposed to President Obama’s economic policies. “The people who run the Republican Party are going to have to learn that moving to the left is not going to win them elections.”

Mr Hoffman, the insurgent Republican, is a married father of three and grandfather of four who runs an array of companies. He is a fiscal conservative who wants to limit the size of government in an era of vast growth in state spending.

Many of his supporters are members of the Tea Party, which sprang up this summer to campaign against higher taxes. For them the Republican Party has abandoned its values.

However the shift to the right is not backed by everyone. Newt Gingrich, a possible presidential aspirant and a hero of the conservative movement, upset many of his right-wing followers when he suggested that the Republicans should embrace centrists to win power.

“If you seek to be a perfect minority, you’ll remain a minority,” Mr Gingrich, the former Speaker of the House of Representatives, wrote on National Review Online. “That’s not how Reagan built his revolution or how we won back the House in 1994.”

Marty Mannix, the Democratic Party county chairman in Plattsburgh, says the intra-Republican battle reminds him of the Democrats’ internecine warfare many years ago. “The Democratic Party went through this in the 1970s. It took a war to wrestle the party from the radical Left. Bill Clinton was the person who brought us to the middle,” he said.

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