Mitt Romney's "major economic address" to the Detroit Economic Club was barely out of his mouth Monday before John McCain's surrogates began slamming the Republican presidential candidate as all talk, little substance.The latest salvo in a presidential race that is growing particularly ugly came as Romney strives to keep a slim lead one day before the GOP primary in Michigan, which is sorely hurting from a downturn in U.S. automotive production.

"Michigan voters shouldn't be fooled by Mitt Romney's latest campaign promises of economic development and job growth. They need to look closely at his record in Massachusetts, where manufacturing job growth was third-worst in the country and taxes and 'fees' increased by over $700 million per year,' said McCain backer and former Massachusetts Gov. Jane Swift, who withdrew from her re-election bid in 2002 under a cloud of voter anger. Her departure made way for Romney to win the nomination and state election.

"Mitt Romney has a reputation of saying anything to win. A comparison of his record versus his rhetoric on the economy shows why," Swift said.

Romney has tried to distinguish his message from McCain's by arguing that he doesn't see the Great Lakes State as a lost cause. McCain has tried to take a pragmatic approach, telling Michigan voters that the automotive industry jobs lost will not return and Michiganders must learn new skills.

But Romney calls McCain's message pessimistic, and says he is unwilling to give up on Michigan.

"I see a vital infrastructure, a skilled workforce, and an innovative spirit all worthy of an optimistic vision and deserving of a leader who will work tirelessly to deliver the power and potential of Michigan and the American people," Romney told voters at the speech entitled "Keeping Michigan and America Economically Strong."

He also cast himself as a Washington outsider who won't be stuck in the political funk of D.C.

"Washington politicians look at Michigan and see a rust belt. But the real rust is in Washington," he said.

Romney said unlike McCain, he is not going to concede Michigan's or the nation's future."A lot of Washington politicians are aware of Michigan's pain, but they haven't done anything about it," he said. "What Michigan is feeling will be felt by the entire nation unless we win the economic battle here. Michigan is a bit like the canary in the mine shaft – what's hurting Michigan, if left unchecked, will imperil the entire nation's economy."

He added that McCain's proposals won't make it easier for Michigan residents or any other American to get past the economic crunch caused by skyrocketing energy prices.

"Senator McCain and Senator (Joe) Lieberman have a bill pending in Congress that unilaterally imposes new high energy costs on U.S. manufacturers, with no safety valve. The Energy Information Agency estimated that this bill would raise electric rates by as much as 25 percent and gasoline prices by 68 cents a gallon. And the cost in American jobs – over 300,000. So it would not only kill jobs, it would make it harder for families to make ends meet," Romney said.

In a multi-point plan, Romney said in his first 100 days as president, he will bring together industry, labor, congressional and state leaders to brainstorm on getting Michigan back on track.

Among his proposals, Romney said he would:

-- Create new tax benefits, including making the research and development tax credit permanent;

-- increase funding five-fold -- from $4 billion dollars to $20 billion dollars -- in national investment in energy research, fuel technology, materials science, and automotive technology;

-- Turn government workforce training programs into personal accounts that can be managed by the workers themselves to gain education at community college or to pay for on the job training in real jobs; and

-- Increase pay for teachers and develop a merit pay system to encourage innovation in skills training.

Romney's tight race against McCain in Michigan is seen as vital to his viability nationally after two second-place showings in Iowa and New Hampshire and a largely unheralded victory in Wyoming. The most recent RealClearPolitics average puts Romney just 0.7 percent above McCain, 27 to 26.3 percent.

Following behind those two candidates is former Arkansas Gov. Mike Huckabee, who has been echoing some of Romney's message on the trail. Campaigning in Augusta, Mich., on Monday, Huckabee also targeted McCain and laid out his origins as evidence that he is the most apt in the GOP field to improve conditions for working-class Americans.

Huckabee said he understood Michigan's economically-depressed woes because he grew up in Hope, Arkansas, with a similar background. Distinguishing the economic class and geographic differences between himself and Romney and McCain, respectively, Huckabee said others in the race don't have a good pulse on working and middle-class Americans or have been insulated in the nation's capital.

"I've been living in the real world while some are living in that insular bubble called Washington, D.C. And if you want someone who believes the status quo is just fine, there are plenty of choices, but if you think we need to bring some true differences and changes in this country that work for working people in this country then we do have a Republican solution," Huckabee told the crowd of only about 100 people.

While the audience was very enthused by Huckabee, the size of the rally paled in comparison to earlier events, where about 1,000 people showed. Huckabee attributed the turnout to last-minute planning.

For his part, McCain seemed super-energetic at his first town hall meeting Monday at the Kalamazoo Christian Academy. Offering his own plans to revive Michigan's economy, McCain very notably did not repeat his earlier claim that jobs in Michigan are gone and not coming back.

Instead, he said Michigan’s status as best in the world can be reinvigorated by turning the auto industry toward battery cars and hybrids. He also discussed retraining displaced workers, speaking in general terms about Michigan having a "different environment" than during the automotive heyday of 40 years ago.

McCain got a standing ovation when he talked about his veteran’s health care plan -- giving veterans a card that allows them to go anywhere they choose for health care.

While both his rivals talked to smaller crowds, before his big speech, Romney addressed one of the largest crowds he has seen -- 2,500 students and faculty at the Grand Blanc High School. Granted, it was a school assembly and the teenagers were required to attend.

While primarily addressing the adults in the crowd, Romney tailored his stump speech for the kids who are too young to remember the oft-mentioned late president and Republican hero Ronald Reagan.

He pushed his success at planning the 2002 Olympics and talked about how his father George Romney, the former Michigan governor who ran for president in 1968, also came to Grand Blanc High as a candidate.

Romney repeated the story about how he met his wife Ann when she was 15 years old, a tale that he says proves that "good things can happen in high school."

He also appealed to the students to work hard, noting that if they think big, they can develop the skills to help the U.S. and Michigan's future.

"One of those qualities is pioneering, pushing yourself to go beyond the boundaries of knowledge, of existing knowledge so you develop new ideas and new enterprises and new businesses and new ways to employ people and to lead this country," he said.

He also spoke in terms of the old game show, "Let's Make a Deal," and said the students have trade-offs to make and could risk their futures if they go down the wrong path.

"Get hooked on drugs and your life's income and your happiness quotient will actually go right down in the basement. There are extraordinary choices that you make in your life which will either be fortuitous and make you happier and wealthier and more fulfilled in your life or there are choices that will make you less fulfilled and you can learn and know what those choices are even as you make them," he said.FOX News' Shushannah Walshe and Serafin Gomez contributed to this report.