The general election came early to South Devon yesterday as an unprecedented postal ballot was used to select a doctor with minimal political experience as the Tory candidate and — almost certainly — next MP for Totnes.

The Conservative Party turned a local political disaster over the extravagant expense claims of Anthony Steen into triumph by asking every voter in the constituency to help to decide who should replace him as the Tory candidate at next year’s election.

Despite fears among local party activists of a low turnout and a dirty tricks operation by the Liberal Democrats, the party was rewarded with a significant response: 16,639, or 24.6 per cent, of the voters of Totnes took part, a level of participation higher than for some council elections.

Sarah Wollaston, 47, a GP, lecturer and married mother of three, beat two rivals with 47.6 per cent of the vote and is on course to keep the seat, with its 2,722 majority, for the Tories.

This is the first time in British politics that a candidate has been chosen by a postal ballot of all the constituents, regardless of their political views, although about 100 Tory candidates have been selected at open meetings where any constituent can attend.

Yesterday’s ballot is the first hint that a new style of politics may yet emerge from the expenses scandal as parties take chances to regain voter trust. It also marks a big step towards an American-style system of choosing political representatives.

Republican and Democrat candidates in some states are selected by voters of all political persuasions in a system known as “open primaries”. In Britain, candidate selection has been jealously guarded by local party activists.

The experiment is, however, unlikely to be repeated too regularly because of its cost of almost £40,000, or £2.40 a vote. Tory insiders said it was justified in Totnes given the circumstances. “Compared to what we would have had to put into the fight without this, it is a good result,” said one.

The party had feared disaster locally over Mr Steen’s £87,000 expense claims for his Devon mansion and subsequent declaration that voters were jealous that the house looked like Balmoral. But the political tide appears to be turning in their favour, with the Liberal Democrats losing control of Devon council to the Tories in June.

Eric Pickles, the Tory party chairman, who oversaw the constituency-wide ballot, said that he would also consider using the internet for such polls in future if ways could be found of ensuring that rival parties could not distort the result.

Some critics said that the Conservatives decided on holding the postal ballot to give the greatest chance of winning to Dr Wollaston, who they claimed was the Tory leadership’s preferred candidate. The GP, a member of the Conservative Party for three years, was the winner with 7,914 votes. Sara Randall Johnson, the chairman of East Devon District Council, came second with 5,495 and Nick Bye, the Mayor of neighbouring Torbay, received 3,088.

An operation by the Liberal Democrats, who encouraged Tory opponents in Totnes to vote for Mr Bye, believing him to be the weakest candidate, failed when he came last.

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