The last four GOP candidates standing are preparing to duke it out for delegates during Super Tuesday contests across 10 states, campaigning in their respective make-it-or-break-it territories as polling gets underway.

Rick Santorum and Mitt Romney have focused their efforts on Ohio, specifically its blue-collar voters, according to a New York Times report. It could be a challenge for Romney however, who lately has taken serious heat for his millionaire gaffes.

From The Times:

At a metal works in Canton and a welding factory in Youngstown, in mailboxes and on the radio, Mr. Romney’s intense focus on these Republican-leaning voters was in evidence on Monday as he made his closing appeal in Ohio - if not as an everyman, then at least as a chief executive who knows how to generate blue-collar jobs and get factories running again.

“Other people in this race have debated about the economy, they’ve read about the economy, they’ve talked about it in subcommittee meetings, but I’ve actually been in it,” Mr. Romney told workers at a guardrail factory in Canton, where he walked among huge coils of steel. “I understand what it takes to get business successful, and to thrive.”

Introducing a new slogan - “more jobs, less debt, smaller government” - Mr. Romney’s factory visits were not just about the Ohio primary. They were part of a broader strategy, hatched at his Boston headquarters, to fight Mr. Santorum for both working-class voters and conservatives on what aides consider to be Mr. Romney’s turf, the economy, rather than on social issues.

Meanwhile, Santorum checked out of the Buckeye State, heading to Washington, D.C., Tuesday to speak to the American Israel Public Affairs Committee. Romney and Newt Gingrich also addressed the group, though both did so via video connection to continue their campaigning elsewhere.

During his stop in Ohio Monday, Santorum made a last-ditch attack on his main rival.

According to The Washington Post:

After weeks of being sidetracked by discussions about contraception, education and other issues, Santorum returned Monday to his criticism of Romney’s conservative record. He questioned whether conservative voters can trust Romney, highlighting the former Massachusetts governor’s health-care law in that state.

“The underlying problem that I hear when I talk to people all over — they say they just don’t trust Mitt Romney to not do what’s the fashionable thing at the moment,” Santorum said in a conference call with reporters. He argued that Romney had shifted with the political winds on issues including global warming and the individual mandate in his health-care plan.

Romney emphasized his economic message and business experience as key to taking on President Obama in the general election. Romney hopes a win in the quintessential swing state of Ohio might finally rally reluctant Republicans around his candidacy.

“I hope that I get the support of people here in Ohio tomorrow, and in other states across the country,” Romney said at a town hall meeting in Youngstown. “I believe if I do, I’ll get the nomination. And then we can start organizing our effort to make sure that we replace President Obama.”

Gingrich has made a heavy push in his Southern states, moving from Georgia to Tennessee in the last few days to potentially revive his dwindling chances of candidacy.

Again, from The Post:

Gingrich showed no signs of slowing down and rejected any suggestion that he may drop out of the contest. Addressing overflow crowds in Tennessee, he rallied supporters by pledging that he would bring the price of gas below $2.50 a gallon.

“Tuesday is going to be a mixed bag, and I think the race will go on,” Gingrich said on CNN. “There won’t be any decisive winner Tuesday.”

Ron Paul appealed to loyal supporters in low-population states like Alaska and Idaho. But according to The Daily Beast's breakdown of the 10 Super Tuesday states, Idaho has a high Mormon presence, which will likely favor Romney, and Alaska is a bit of a toss-up.

What may be the crucial indicator are the results in the other Super Tuesday races. Alaska is a caucus, not a primary and when voters show up, they’ll already have a sense of what’s happened elsewhere. As a result, the battle there between Romney and Paul becomes near impossible to predict.

Polling is already underway for primaries in Georgia, Massachusetts, Ohio, Oklahoma, Vermont, Tennessee and Virginia. The North Dakota caucuses convened at 5:30 a.m. CT/MTthis morning, CT/MT. Idaho's caucus will convene at 7 p.m. MT, and Alaska is set for 4 p.m. Alaska time (4 hours behind ET).

Check out Neon Tommy's live blog as results roll in later today.

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