Mitt Romney's competitors are closing in on his territory.

The former Massachusetts governor and Michigan native has, more than any other GOP presidential candidate, staked his campaign on his showing in the Jan. 15 Michigan primary. Banking the race on his home turf, Romney has pulled ads in early voting South Carolina and Florida to concentrate on the state, hoping a win there will finally give him a springboard after second-place finishes in Iowa and New Hampshire.

But rivals John McCain and Mike Huckabee left South Carolina to compete for support in Michigan Saturday, and polls show the state is by no means a lock for Romney.

Huckabee even announced an endorsement from the former head of Romney's Michigan Faith and Families coalition -- state Rep. Fulton Sheen (R), who cited Romney's criticism of the Fair Tax, a national retail sales tax proposal Huckabee supports.

"I've got a much larger count than anyone in the state so I'm happy with the ones I've got," Romney said of the defection in Marshall, Mich., late  Saturday afternoon.

Looking to head off his rivals and appeal to labor interests, Romney continued to underscore the need to get Michigan out of its "one-state recession" and stressed his roots in the state. His father, George Romney, was a three-term Michigan governor in the 1960s. He even ran into his first-grade teacher Saturday.

"For me Michigan is personal. It is personal because this is where I was born and raised. It's personal because this is where my mom and dad lived their lives and are buried," Romney said Saturday morning in Traverse City, Mich., speaking to an enthusiastic crowd of 250 people. “I’ll make sure Michigan comes back again. I will give it my all. I come from a good line of Romney’s who care about people. I care about the future. I love this great land.”

He again pressed that he can get Michigan out of its "recession" and revitalize the automobile industry.

"I'm not willing to say it is okay for jobs to leave Michigan. I'm not willing to give up on Michigan," he said. "I'm not willing to give up on the automobile industry and say, 'Oh it's just gone away' ... No no no."

Economic issues are a focal point heading into Tuesday's primary because Michigan's unemployment rate, at 7.4 percent in November, is the highest in the country by a full percentage point. It also is about 50 percent higher than the national average.

Bureau of Labor Statistics figures show the state shed more than 76,000 jobs in the 12 months ending in November, a period in which the national economy added 1.5 million jobs.

Citing Romney's commitment to the state's economy, Michigan's Grand Rapids Press endorsed him Friday.

Click here to read the Grand Rapids Press endorsement.

Romney also made an unscheduled stop in Ypsilanti at a GM plant where 200 layoffs were announced the day before.

But polls show McCain is enjoying a widespread surge in popularity following his win in New Hampshire Jan. 8. And Huckabee is still maintaining strength after winning Iowa the week before.

Michigan poll averages on RealClearPolitics.com show McCain with 25.8 percent, Romney with 22.4 percent and Huckabee with 16.8 percent in the state. Former New York Mayor Rudy Giuliani, former Tennessee Sen. Fred Thompson and Texas Rep. Ron Paul are all polling in the single digits in Michigan.

Romney criticized Washington Saturday for not acting on Michigan's economic problems -- a none-too-subtle shot at McCain, who has said that some of Michigan's lost jobs are gone forever. He defended his comment during a raucous rally before 400 supporters in Warren.

"I like and respect Governor Romney, but you know, he's run weeks and weeks of negative attack ads against me. It didn't work when he attacked Governor Huckabee in Iowa, and it didn't work when he attacked me in New Hampshire, and I don't think it will work here in Michigan, but that's a choice he's made," McCain said.

He also mentioned a Detroit News headline Saturday: "Experts Back Up McCain's Jobs Claim."

Huckabee, a former Southern Baptist minister, started his day with a prayer breakfast in Grand Rapids, before attending a rally in the city.

"I want to win Michigan real badly. Really, really want to win Michigan and no one expects me to ... come in closer than a very distant third, and if you look at dynamics John McCain won 2000, Mitt Romney grew up here, his dad was governor here, and let's face it the name Huckabee doesn't open any doors," Huckabee said. "To win Michigan or to be in the running is a huge deal."

At the prayer breakfast he emphasized his opposition to abortion rather than touching on economic talking points, as he urged about 100 pastors in Grand Rapids to support him and use their address books and e-mail lists to mobilize others.

"I don't presume that you will support me because of a common faith," Huckabee told them. "I know that I have to earn that. But I also recognize this is a unique opportunity. For a long time, those of us who are people of faith have been asked to support a candidate who would talk to us. But rarely has there been one who comes from us."

He added, "Life is in the balance."

While only 34 delegates are up for grabs Tuesday, the candidate activity highlighted the state's importance in the battle for momentum.

Another second could have special impact on Romney, given his homestate connection. He has tried to prevent that with heartfelt pleas for votes and a promise that as president he will give the state special hometown attention.

FOX News' Shushannah Walshe and The Associated Press contributed to this report.