DeLay said he would continue to serve in his suburban Houston district. He will seek a 12th term this fall, in what promises to be a tough campaign against Nick Lampson, a Democrat and a former congressman.

While members pushed to oust DeLay in part out of fear about their own reelection prospects this fall, the revolt that led DeLay to step aside could send the opposite message to voters. DeLay's decision to resign on the heels of the Abramoff plea might suggest a "hint of guilt," said Julian Zelizer, a congressional historian at Boston University.

"The dam has broken," Zelizer said. "Democrats clearly have a big opportunity to develop the theme of Republicans and the culture of corruption. This is a big blow to the Republican Party."