John F. Kerry repeatedly questioned President Bush's maturity and temperament Saturday as the rivals tried to capitalized on their second debate, while a reenergized Bush vowed not to let the senator hide from his political past.

Both camps found enough in Friday night's debate to claim victory and to hit the weekend hustings with big smiles and new material aimed at maintaining the offensive before the candidates' final face-off Wednesday in Arizona.

Kerry, referring to a moment when Bush was so eager to respond that he interrupted the moderator, recalled for a rally audience of 10,000 on a community college lawn that he had become "a little worried at one point -- I thought the president was going to attack Charlie Gibson."

"America needs new leadership -- not a single-minded leader, but a clear-headed leader. Not a headstrong leader, but a well-reasoned leader," Kerry said. The Massachusetts senator criticized Bush for "refusing to show the maturity" to be patient in building a bigger alliance on Iraq.

Both candidates stayed overnight in St. Louis after the debate. While Kerry headed for Ohio and Florida, Bush used appearances in Missouri, Iowa and Minnesota to unveil a new attack mantra for the senator's positions and programs. In a variation on a line he used twice in the debate, Bush repeatedly said: "He can run, but he cannot hide."

Kerry's campaign, trying to draw attention to the occasionally loud answers from Bush that his aides described as feisty, sought to portray the president as unhinged, issuing a three-page document describing him as "Nixon-like" and "hot under the collar."

Democratic strategists said Bush's confident sense of his own purpose is his most formidable quality, and the senator's remarks were aimed at undermining the president's image of resoluteness. "There's a point where that walks right up close to pig-headedness, and that's the danger for them," Kerry adviser Michael McCurry told reporters aboard the candidate's plane.

Kerry spoke on a crisp autumn afternoon on a stage piled with hay bales, pumpkins and baskets of apples. He said that the "most stunning moment of the whole evening was when George Bush was asked to name three mistakes that he has made."

Bush, who had said during an April news conference that he could not think of a mistake, did not point to anything specific, but he said that there are "lot of tactical decisions" in war that historians may question, and that he has "made some mistakes in appointing people, but I'm not going to name them -- I don't want to hurt their feelings on national TV."

"The president couldn't even name one mistake," Kerry crowed. He joked that now "people are standing around wondering" which Cabinet member the boss was talking about, and said, "I just want him to know I agree with him about those bad appointments."

"Every time someone has stood up and told the truth in this administration, they've left -- every time," Kerry said, referring to former Treasury secretary Paul H. O'Neill, former economic adviser Lawrence B. Lindsey and retired Gen. Eric K. Shinseki, former Army chief of staff.

The senator's aides disclosed on Saturday that during the final phase of the campaign he will stress his determination to fight for the middle class, and his speech at Lorain County Community College was laced with populist rhetoric. "I'm going to be a president who fights harder for your jobs than I do for my own," he said.

Bush, modifying his basic stump speech slightly for the second time in a week, said in St. Louis that Kerry's campaign-trail and debate statements about Iraq, health care and taxes "just don't pass the credibility test."

"With a straight face, he said, 'I've only had one position on Iraq,' " Bush noted at a breakfast meeting for Matt Blunt, Republican candidate for Missouri governor. "Who is he trying to kid? He can run, but he cannot hide." Bush repeated the line at a huge outdoor rally in a minor-league baseball park in Waterloo, Iowa, and later in Chanhassen, Minn., during a one-day tour of Midwest swing states. By his third repetition of the phrase, supporters in Chanhassen, outside Minneapolis, chanted along with the president.

Vice President Cheney spent the weekend in the pivotal state of Florida and next week will make his first trip to New Jersey, a Democratic stronghold in which Bush has pulled even with Kerry in some polls. In Jacksonville, Fla., Cheney criticized Kerry for a "message of indecision and confusion," not just during the campaign but during Friday's debate.

In Detroit, Democratic vice presidential candidate John Edwards attacked Bush's record on job creation, echoing the themes that Kerry used during the debate. He received some of his most sustained applause when he pointed out that Michigan has lost the most jobs of any state in the nation during the Bush administration, and that Kerry's plan would reverse these losses by providing tax cuts for companies that stay in the United States and do not "outsource" jobs to other countries.

"They say they're creating jobs. Where?" Edwards asked a roomful of energized Democrats who congregated at a community center on Detroit's east side. "The jobs they are creating are . . . fast-food jobs, janitorial jobs, minimum-wage jobs."

Even as he crafted his remarks about the health of the nation's economy, Edwards continued his attacks on the administration over its handling of the war in Iraq. "Iraq is a mess because of two men: George Bush and Dick Cheney," he later told a crowd in Saginaw, a manufacturing town of 60,000 an hour north of Detroit. "They are still not taking any responsibility for what's happened."

Farhi is traveling with Bush. Staff writers Ovetta Wiggins, traveling with Cheney, and Chris L. Jenkins, traveling with Edwards, contributed to this report.