Rising to prominence while attacking his own party, former Vermont Gov. Howard Dean (search) said Tuesday that winning the presidency in 2004 means not imitating President Bush.

"The first way we're going to beat George Bush is not to try to be like him. You cannot beat George Bush by trying to be 'Bush lite,'" the Democratic candidate running for the party's presidential nomination told laborers attending the Communications Workers of America (search) convention in Chicago.

"I believe too many people in my party for too long caved in out of fear for high poll ratings, have been terrified by [talk radio host] Rush Limbaugh and all those people, beating up on unions, 'Yes, sir, we are afraid to stand up to the right wing,'" Dean said.

Five of the nine candidates have appeared at the two-day convention, but Dean seems to have captured the imagination of the liberal left base of Democratic donors.

Ata rally on Tuesday night in New York City, Dean also rapped Bush for the deficit, which the Congressional Budget Office projected Tuesday would reach $480 billion in 2004.

"We will have the first half-trillion-dollar deficit in the history of the world because this president can't handle the economy," Dean told a raucous rally.

All the candidates have launched attacks for what they describe as Bush's mishandling of post-war Iraq, but Dean said he has the formula for defeating him and bringing new leadership to the White House.

"The way to beat George Bush is to get the 50 percent of the people in this country who have given up on voting a reason to vote again. That's how we're going to beat him," he said.

Dean shook up the primary race this summer, collecting the most money in the fund-raising period that ended June 30 and launching a successful challenge this month to raise $1 million on the Internet.

Dean campaign manager Joe Trippi said Dean is expected to pull in another $10.3 million in the quarter ending Sept. 30, a record matched by only one Democratic presidential candidate in the year before an election — Bill Clinton in 1995. Privately, Dean aides said the $10.3 goal is a conservative estimate.

Dean's rise has been witnessed by thousands of voters who have shown up around the country at his "Sleepless Summer" (search) tour locations. Many agree that the Democratic Party has gone soft and want Democratic candidates to get tougher.

Though he still has yet to win the Democratic nomination to challenge Bush, Dean said the process of getting there means campaigning in all 50 states, starting with an extensive television ad buy in non-traditional locations.

Dean announced that he is spending more than $1 million on an ad blitz in markets in six new states — South Carolina, Arizona, New Mexico, Oklahoma, Washington and Wisconsin — all states that don't normally see advertising this early in the campaign season. The ads begin airing on Friday.

In the ad, Dean touts his record as governor, promises to "take the country back" and urges voters to log onto his Web site. He also boasts of his opposition to war in Iraq, which rivals argue could hurt him if he were to go head-to-head against Bush.

"I opposed the war with Iraq when too many Democrats supported it because I want a foreign policy consistent with American values," Dean says in the ad.

His campaign said the ad buy is big enough that the average viewer in the chosen markets will see Dean's add run 10 times over the 17-day run.

Dean aides admitted their express purpose is to steal thunder from and torment Dean's closest rival, Massachusetts Sen. John Kerry, who is formally announcing his candidacy in a two-day, four-state swing next week.  

But Dean's momentum has created a problem for him, said Kerry backers. Dean had pledged to campaign within the public finance system. With the unexpected surge in popularity, he has found himself backing away from that pledge and possibly rejecting taxpayer money to avoid spending limits. 

"The Dean campaign's sole strategy is momentum and buzz," said Jim Jordan, Kerry's campaign manager. "Given the confines of the state spending limits, spending $2 million on TV in the summer — before most voters have checked in — I think is a fairly extreme resource allocation decision."

Aides in rival camps also said Dean may end up spending as much money as he earns through the ad buy. If history is any indication, however, Dean may end up on the plus side. As the first candidate to air television ads in Iowa and New Hampshire, in June, Dean raised tens of thousands of dollars and catapulted his campaign.

The decision to make a large ad purchase has forced Kerry to expand his ad buys in September. Aides said he is considering several options, including buying ads in as few as two states and as many as six.

While Kerry and Dean are leading the polls in most states, other candidates are also considering their strategies.

North Carolina Sen. John Edwards, who is the only other candidate airing ads in Iowa, New Hampshire and South Carolina, is not planning on expanding beyond those three states in September.

Missouri Rep. Dick Gephardt intends to air ads in Iowa and New Hampshire next month.

Sen. Joe Lieberman of Connecticut has made no decisions and may not air ads in September, aides said.

Sen. Bob Graham of Florida has begun to film for his ads, but has not decided when to begin broadcasting them. He has had trouble raising money.

Fox News' Carl Cameron and The Associated Press contributed to this report.