What happened? Hurricane Katrina served as the kick-start to what wound up being a terrible 14 months for Republicans. The mishandling of the disaster response was followed by the indictment of Majority Leader Tom DeLay (Texas) on state campaign finance charges; the disastrous Supreme Court nomination of Harriet Miers; and the indictment of I. Lewis "Scooter" Libby in the CIA-leak case. By January 2006 Jack Abramoff had pleaded guilty to bribing unnamed House Republicans and GOP aides, and the Iraq war continued to sink deeper into a quagmire. On Election Day 2006 Democrats didn't lose a single seat and then managed to pick-up 30 GOP seats, thus ending the House Republican reign of the previous 12 years.
Here's the line-up card of the House GOP leadership team from August 2005, with a rundown of what has happened to them since:
http://blog.washingtonpost.com/capitol-briefing/2007/08/house_gop_leaders_fall_from_po.html