He was 37, with just a year's experience in the 80-member Assembly, when he won a three-way race for speaker. Democrats gambled that he would learn the job quickly and be speaker long enough to accrue power equal to that of the governor and Senate leader.
The risk paid off. Under Nunez, the Assembly has upstaged the more staid, experienced Senate.
Last July, for example, Nunez cajoled Republicans into approving a state budget, then dismissed the Assembly for summer recess, leaving the Senate to debate the $145-billion spending plan for another month in the Sacramento heat. The final budget was two months late and virtually the same as that passed by the Assembly.
Democratic colleagues praise Nunez's energy, passion and quick grasp of policy. He ruled with a strong hand -- and, occasionally, a temper.
Kevin McCarthy, a Bakersfield Republican who led the minority caucus during the early years of Nunez's tenure and is now a congressman, remembers the speaker slamming his office phone hard enough to break it after McCarthy refused to follow an order.
But "he's incredibly charismatic," said Assemblyman Mark DeSaulnier, a Concord Democrat. "He's what some people would call a vitalist, full of energy and life, and he's strong-willed, so naturally you're going to have some friction from some members and some people outside."
People embraced Nunez, and he returned the favor, said former Assemblyman Rudy Bermudez, a Norwalk Democrat who served under Nunez for two years. He noted that Nunez entrusted important posts to then-Assembly members Jenny Oropeza (D-Long Beach) and Dario Frommer (D-Los Feliz) after he outmaneuvered them to become speaker.
"He didn't have people back-stabbing him," Bermudez said, "and a lot of it was because of how he mended fences."
Republicans described Nunez as a "bare-fisted partisan." But they also said he aggressively defended the prerogatives of the institution.
When one state senator broke a promise to the Assembly to make changes to a bill he was sponsoring, Assemblyman Chuck DeVore (R-Irvine) remembered, retaliation from Nunez was immediate: He killed the senator's bill.
Like several other members, DeVore said Nunez's staff used threats and intimidation when necessary to advance an agenda. "You can either be a doormat or a dictator," he said, "and I think he chose the latter route."
Nunez cultivated at least one Republican: Gov. Arnold Schwarzenegger. But the bond was not instant. Initially, Nunez once said, the two mixed like "oil and water."
But to their mutual benefit, they eventually warmed to each other. What followed was a bumper crop of ambitious legislation, especially in 2006.
"Speaker Nunez and I have had a lot of successes together," Schwarzenegger said Friday through a spokesman. " . . . I wish him all the best in this next phase of his life."
The two agreed on laws to raise the minimum wage from $6.75 to $8 an hour, to allow phone companies to sell pay TV and to reduce prescription drug costs for about 6 million uninsured Californians.
To great fanfare, they struck an accord to scale back California's greenhouse gas emissions by 25%. And they teamed on a sweeping $14.9-billion plan to extend healthcare coverage to most uninsured Californians -- but it was defeated by senators concerned that it could drain state coffers.
That work may not be over, Nunez said last week: "I want to figure out outside this building how I can build the types of coalitions that can get major issues like healthcare done."
As one of five top leaders negotiating the annual state budget, Nunez successfully resisted most cuts that would have hurt the poor, disabled and elderly. And he surprised many observers by being willing to upset organized labor by approving tribal gambling compacts it opposed and embracing provisions in healthcare legislation that unions said were onerous to workers.
Nunez described himself as a champion of the people's interests, but sometimes the public paid for moves that could help special interests.
Pushed vehicle fees
After midnight on the final day of last year's legislative session, Nunez pushed through a bill that increased registration fees for cars and trucks by as much as $10. Although the money was to subsidize clean-fuel development, opponents said the funds could be used by oil companies to pay for pollution-reduction measures they were already required to take. Nunez has since said a giveaway to oil companies was unintended and has written a second bill, now pending, to clarify the law.
Nunez's final endeavor could fundamentally change the Legislature -- and correct one of his most marked failures. In his seven remaining months as an Assemblyman, Nunez will try for a second time to ease term limits so legislators can stay in office longer. He will tie the proposal to one that would transfer to an independent panel the Legislature's power to draw its own districts.