John Bercow, the Tory MP for Buckinghamshire, has won the race to succeed Michael Martin as the new Speaker of the House of Commons.

He won the third round of voting last night, beating his nearest rival Sir George Young by 51 votes.

The MP has been something of a leader for gay rights in his party since changing his views on the gay age of consent in 2000, something which has earned him mistrust from some Conservatives.

In 2007, he had to fend off rumours he was planning to defect to Labour.

Bercow also spoke out against Section 28, which banned discussion of homosexuality in schools, and urged the Conservative Party to become a “champion of gay rights”.

A former member of far-right group The Monday Club, he led calls for Tory MPs to be banned from joining the club while in Iain Duncan Smith’s shadow cabinet.

In 2002, he resigned from the frontbench when Tory MPs were instructed to vote against allowing gay couples to adopt children.

In January of this year, he argued that the Conservatives needed their own Harriet Harman figure to make parliament more representative.

Writing in the Guardian, he said: “In truth, for generations the selection process has discriminated against women and minorities, choosing instead to hand out jobs for life to mediocre men who went to the right school, spoke with the appropriate accent or were suitably well-heeled.”

His transformation from national chairman of the sometimes radical Federation of Conservative Students to gay rights defender has been credited in part to his marriage to Labour sympathiser Sally Illman in 2002.

However, he has said his conversion began long before that, recalling his “bone-headed” views on race while in the Monday Club.

In another display of modernism, Bercow said today he will not wear the traditional dress worn by Martin.

He said: “I think it is perfectly proper that the Speaker should wear a business suit and have a simple and unfussy gown over that suit and that is what I intend to do,” he said.

“That is very much a personal choice for me. I think that is right for the spirit of the times.”

He was criticised in the expenses scandal for “flipping” his second home to avoid capital gains tax on the sale of two properties in 2003. He has since agreed to repay £6,500 to HM Customs and Revenue.

However, he said today he will not claim the parliamentary second home allowance while in the post.

He has also pledged to bring more openness to how MPs’ expenses are published and to “move away from some of the boorishness that I think has disfigured the place”.