His Democratic opponent, Sen. John Kerry of Massachusetts, called for deeper middle-class tax cuts than the president has proposed and described his Republican critics as "the most crooked ... lying group I've ever seen."
Speaking in Ohio, a state that has lost more than 200,000 jobs since he took office, Mr. Bush blamed the nation's economic woes on factors beyond his control — a recession that officially started just after his inauguration, business scandals he said were brewing for years and the terrorist attacks of Sept. 11, 2001.
Mr. Bush tried to project empathy for displaced workers, repeatedly saying that he understood the anxiety felt by Americans who are swept up in a changing economy. But, he told a conference of businesswomen, "some politicians in Washington see this new challenge and yet they want to respond in old ways."
"Their agenda is to increase federal taxes, to build a wall around this country, and to isolate America from the rest of the world," Mr. Bush said on his 15th trip to this critical electoral state.
"That old policy of tax and spend is the enemy of job creation; the old policy of economic isolationism is a recipe for economic disaster," he said. "Americans have moved beyond that tired, defeatist mind-set, and we're not going back. There's a better way."
Mr. Bush never directly mentioned Kerry, who secured the delegates needed to claim his party's nomination with a sweep of four Southern primaries Tuesday night, according to CBS News estimates.
As the president spoke to a friendly audience, several hundred protestors stood across the street carrying signs calling for more jobs. One man's placard read "Bush making millionaires into billionaires," reports CBS News Correspondent Peter Maer.
While the economy is a central issue in the campaign, the White House described Mr. Bush's Ohio trip as an official visit, meaning taxpayers pick up the costs.
Speaking Wednesday in Chicago, Kerry toughened his comments about his GOP critics after a supporter urged him to take on Mr. Bush. "Let me tell you, we've just begun to fight," Kerry said. "We're going to keep pounding. These guys are the most crooked, you know, lying group I've ever seen. It's scary."
Kerry spokesman David Wade said the senator was referring to Republican critics in general. "The Republicans have launched the most personal, crooked, deceitful attacks over the last four years," Wade said. "He's a Democrat who fights back."
In a speech to top leaders of the AFL-CIO, Kerry said a "Bush Tax" stemming from the president's economic policies has driven up costs for working families. He vowed to reverse that trend while asking those making more than $200,000 a year to pay the same taxes they paid under President Clinton, effectively repealing portions of a tax cut Mr. Bush pushed through Congress.
Kerry also proposed creating a $50 billion fund to help states provide relief from state and local taxes for working families that he said have been struggling.
"Under George Bush's policies, middle-class families are paying more," he said. "America's middle class can't afford a tax increase. That's why we're going to give the middle class a tax cut."
Kerry won primaries Tuesday in Florida, Texas, Mississippi and Louisiana, largely without major opposition. He won about 75 percent of the vote in Florida and Mississippi, and about two-thirds in the other states.
The wins give Kerry 2,174 delegates (including so-called "super-delegates"), according to a CBS News tally, surpassing the 2,162 needed to win the Democratic nomination.
Kerry was returning to Washington on Wednesday to meet with Howard Dean, the former Vermont governor who had been one of his top rivals for the nomination. He was scheduled to meet Thursday with John Edwards, who left the campaign after the Super Tuesday elections of March 2.
Dean is prepared to campaign for Kerry and ask his own contributors to donate to Kerry's campaign, said officials familiar with the meeting. Aides are expected to spend a week or so planning an endorsement, the officials said.