In hindsight, it all seems so ironic. If there was one thing Florida congressman Mark Foley seemed to abhor, it was child sex offenders - 'America's most depraved' he called them. As co-chairman of the Congressional Missing and Exploited Children's Caucus, the six-term Republican authored legislation to block child pornography, repeatedly warned parents that the internet had become 'a new medium for paedophiles' and became a vocal proponent for the overhaul of sexual predator laws. 'For too long, our nation has tracked library books better than it has paedophiles,' he declared on the television programme America's Most Wanted last year, vowing to root out child sex offenders. 'If I was one of those sickos, I'd be nervous,' he added. What no one knew at the time - or they were not telling - was that Mr Foley was the kind of 'sicko' he spent so much of his career crusading against. In a series of e-mails and instant messages sent to teenage male congressional pages - office messengers on Capitol Hill - the 52-year-old is revealed to have engaged in chats that ranged from awkwardly inappropriate to deeply pornographic in their content. As the avalanche of evidence poured in to the public domain, some of it dating back to 2003, Mr Foley resigned and went into hiding. 'I am deeply sorry and I apologise for letting down my family and the people of Florida I have had the privilege to represent,' he said in a written statement, seeking to explain it by first claiming to be an alcoholic - to the surprise of friends, colleagues and relatives, who know of no such problem - and then asserting that, as a child, he was sexually abused by a clergyman. He is being investigated by the FBI and the Justice Department over his e-mails and could be prosecuted for preying on under-age children under the very laws he helped enact. But it is the political earthquake he has left behind that is of greater consequence. The scandal has left the Republican leadership in meltdown with just five weeks to go until the mid-term congressional elections. Even before the sordid revelations, the Republicans were expecting to lose seats in the House of Representatives in November, but hoped they could limit the drop to fewer than 15, allowing them to maintain control. About 30 seats are in play - among them now Mr Foley's previously 'safe' seat in Florida's District 16, a Republican stronghold for 24 years, where he won his sixth term in office in 2004 with 68 per cent of the vote. With the top echelons of the party hierarchy at the centre of a major inquiry as to who knew what, and when, about Mr Foley's behaviour - and the answer appears to be that they knew quite a bit, but did nothing - the fallout from 'Foleygate' has spread far wider than District 16. House Speaker Dennis Hastert and the chairman of the National Republican Congressional Committee, Thomas Reynolds, could both end up with their heads on political stakes, and the scandal has strong potential for influencing the balance of power in Congress as voters register both disgust and distrust at the polls. Mr Foley is the fourth Republican congressman to resign this year; Tom DeLay of Texas, the former majority leader, stepped down over campaign finance irregularities; Bob Ney of Ohio admitted to federal bribery charges and Randy Cunningham of California was imprisoned for bribery. 'This might be the straw that breaks the camel's back, that one more drop in the bucket that tips the level. Given how ugly Foley's story is, the public has just had it up to their necks with this arrogance of power,' said Robert Watson, a political scientist at Florida Atlantic University. 'A week ago, no one had District 16 on their radar. But five weeks to go until the elections and this story is snowballing. We'll be talking about it right up to when we go into the voting booths. The Republicans are really scrambling now.' Foley was born in Newton, Massachusetts, in 1954, but has lived in Lake Worth, Florida, since he was three. At the age of six, seeing his local congressman working an adoring crowd at a local shopping centre, he edged closer and ended up being paid US$5 to hand out campaign brochures. He resolved there and then that he would pursue a career in politics. 'For whatever reason, it stuck. That was my dream,' he recalled years later. By the age of 17, he was running his own car-cleaning business after school, and after graduating in 1973, his father got him a loan so he could go into business running a restaurant, The Lettuce Patch, with his mother, Fran. He later became a real estate broker. In 1983, he was elected vice-mayor of Lake Worth, followed by a seat in the Florida State House seven years later. In 1995, he won a seat in the US Congress, where despite being a Catholic he exercised a pro-choice stance and supported the death penalty. He became deputy House whip and got involved in issues ranging from small business advocacy to farmland protection and was a member of several political groups including the Congressional Caucus on Hong Kong, a bi-partisan faction in which legislators could discuss issues concerning Hong Kong. But he carved out his main policy niche as a crusader against child pornography, presenting himself as a protector of exploited children and crafting an image for himself as a saviour of moral values. When Bill Clinton's affair with White House intern Monica Lewinsky rocked Washington in 1998, Mr Foley took the floor during a congressional debate to denounce the president as 'vile'. 'It's more sad than anything else to see someone with such potential throw it all down the drain because of a sexual addiction,' he railed to a Florida newspaper at the time, never realising that the quote would effectively prophesy the downfall of his own career eight years later. 'Mark Foley wasn't someone who was beloved, but he was liked,' Dr Watson said. 'He had a very pleasant, non-egotistical demeanour, self-effacing, a good sense of humour. He waved at everyone and showed up at community events. He was one of those guys whose constituents took pride in calling 'our home town congressman'.' He refers to his sister Donna, who has spent years at his side as campaign manager, as his 'surrogate wife'. He has never married and his homosexuality - to which he admitted this week - has long been an open secret in Washington circles, despite him having shot down the rumours in 2003 as 'revolting'. Mr Foley's career is at an end and the Republicans in crisis. The Democrats look almost certain to become winners in the Foleygate affair, a scandal that appears to be their 2006 'October surprise' - the name given to a shock political event or revelation that happens to burst forth just before the November elections. Mr Foley's e-mails appear to have been unearthed by Citizens for Responsibility in Ethics in Washington, a watchdog group bankrolled by billionaire George Soros and Daniel Berger, one of the Democrats' most prolific donors. The scandal has become a platform for moral values groups, whose campaign for a more wholesome society and the protection of innocence is, ironically, a theme Mr Foley once championed. 'When a 16-year-old boy is not safe from sexual solicitation from an elected representative of the people, we should question the moral direction of our nation,' said Tony Perkins, president of the Family Research Council. 'If our children aren't safe in the halls of Congress, where are they safe?'