Kerry appeared confident as polls in Wisconsin showed him with a comfortable lead over Dean and John Edwards, his other major rival for the state's 72 delegates.
The frontrunner continued to ignore Dean and Edwards as he criticized President Bush, labeling the president missing in action on the economy. He ridiculed the president on Monday for taking a trip to the Daytona 500 auto race in Florida at a time when the economy should have his undivided attention.
"We don't need a president who just says, 'Gentlemen, start your engines,'" Kerry said. "We need a president who says, 'America, let's start our economy and put people back to work.'"
A CBS News poll showed that if the election were held today, Kerry would beat Mr. Bush 48 percent to 43 percent. But Mr. Bush would defeat Edwards 50 percent to 41 percent and Dean by a much more sizeable 54 percent to 37 percent margin.
Kerry's Democratic rivals swept across Wisconsin on the eve of a primary that could offer the last chance to blunt the momentum that Kerry has built in piling up 14 wins in the first 16 contests.
Dean's own national chairman, Steve Grossman, left the campaign Monday amid speculation he would join Kerry. But he denied reports that his campaign was disintegrating.
"I think we're in reasonable shape," Dean told the CBS News Early Show. Noting that Kerry has momentum, Dean said the key issues in the state, jobs and healthcare, "are good issues for me. It's all optimistic."
Dean declined to say Tuesday whether Grossman had quit or had been fired after telling reporters that Dean was likely to leave the race if he lost in Wisconsin.
Instead, Dean contended his campaign remained solid with more delegates than anyone but Kerry, the strongest presence in Wisconsin of any candidate, and a better infrastructure than any other campaign for the Super Tuesday contests March 2.
Asked if he would remain in the race, Dean replied, "I am going to be around tomorrow. We'll be in Burlington. We're going to talk about what we're going to do in the future of the campaign. We're going to keep going. We've got good organization through March 9th in Illinois and certainly for Super Tuesday."
The departure of Grossman obscured Dean's message in a state with a tradition of supporting liberals, mavericks and Washington outsiders — a state Dean has said he badly needed to bounce back from a long string of losses.
The move was the second shake-up in recent weeks in a campaign that had been the presumptive front-runner but then failed to win a single primary or caucus. Former campaign manager Joe Trippi was forced out earlier.
While he was generally upbeat, Dean's aides described him as torn between reaching a pragmatic conclusion that the campaign is coming to a close, and his emotional attachment to a race in which he's been running for well over a year.
On Tuesday, Dean repeated his mantra that other Democrats might also defeat Mr. Bush but only he can offer real change, he added, "We're not going to do anything to tear down the Democratic nominee. If Sen. Kerry is the nominee, we need to support him."
"I'm not going to do anything to disrupt the passage of the nominee to the White House," Dean told the Early Show.
Edwards, who won the South Carolina primary two weeks ago, expects Dean will drop out after today, leaving the race for the democratic nomination down to Edwards versus Kerry.
For his part, the North Carolina senator tried to sharpen the differences he has with both Kerry and Dean on trade issues, and he said it would be easier to get his message out now that the Democratic field has shrunk to half the size it began with.
"Voters will get a better sense of who we are and what the differences are between us," said Edwards.
Edwards said it was not too late for a surge in polls that have given Kerry a wide lead in the latest primary test.
"It's not too late because this primary process is going well into March," Edwards said.
Edwards was making plans for a campaign post-Wisconsin, scheduling a fund-raiser in New York for Wednesday night and announcing plans for a three-day swing through five states that will hold primaries on Super Tuesday.
Trade could be a powerful issue in Wisconsin, a state that has lost nearly 80,000 manufacturing jobs since Mr. Bush took office, CBS News Correspondent Byron Pitts reports.