Because he knew Republicans can't win on the issues, even in Texas - a state dumb enough to elect a psuedo-fundie ex-drunk as governor - he broke decades of precedent to gerrymander districts in the state. All to artificially inflate the Republican majority.
I can understand a man like Delay. He is a simple criminal, who was lucky enough to get otherwise honest people to vote for him. What I don't understand is the mass of Republicans who see this two-bit con artist dragging their party through sewage, and they are unwilling to speak out about him.
Yahoo! News - Republican Leader Denies Wrongdoing Over Trips
"U.S. House of Representatives Majority Leader Tom DeLay, admonished by his chamber's ethics committee last year, on Tuesday denied any wrongdoing in taking two foreign trips paid for by outside groups."