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Former Massachusetts Gov. Mitt Romney notched two big wins Tuesday, upping his Republican presidential delegate count and taking modest-plus momentum into the week leading up to Super Tuesday on March 6.

With the Michigan and Arizona primaries in the history books as Romney's fifth and sixth victories, we're looking ahead to Super Tuesday, when presidential contests will be held in 10 states and 413 delegates will be up for grabs.

The star of the show? The hotly contested race in Ohio, where Rick Santorum and Mitt Romney are engaged in a battle royale for its trove of 63 delegates and Midwest bragging rights.

But candidates are also aggressively prospecting for votes and delegates from Idaho to Vermont; from the socially conservative South, where Newt Gingrich will attempt to revive his campaign with a win in Georgia (which he represented for two decades in the House); to caucus states like North Dakota, where Ron Paul has staked his presidential future.

But if race predictions hold, Super Tuesday is unlikely to prove determinative, and the four remaining Republican candidates are expected to continue their delegate-by-delegate slog to amass the 1,144 needed to secure the nomination.

"It's been the calling card of this cycle — incremental gains," says Josh Putnam, a political scientist who, with his blog, FrontloadingHQ, has emerged as the election season's guru for all things related to the primaries and delegate counts.

"What I'm looking at is who can win outside their comfort zone next week," Putnam says.

Predicting outcomes and delegate allotment is difficult, he says, given Republican Party rules that in most states award delegates based on how candidates perform in individual congressional districts, as well as statewide, and not simply by a proportion of the overall vote.

That being said, here's our look at the four candidates and their Super Tuesday prospects — at least at the moment, and with the caveat that if past is prologue, the race promises many more twists and turns. Perhaps even before next Tuesday.

Rick Santorum

The former Pennsylvania senator is currently topping polls in next-door Ohio, with an average lead over Romney of 8.3 percentage points, according to surveys compiled by RealClearPolitics. Ohio, Putnam says, is the "big gem" of next week's contests, "a true battleground and Midwest test."

Romney's Ohio support, at about 26 percent, has barely budged since the beginning of the year, while Gingrich has been up and down. The former House speaker briefly led Ohio state polls late last year, but now, like Paul, is barely registering in double digits.

Santorum also has risen to the top of the polls in Oklahoma, where Gingrich is a distant second, and in Tennessee, where Romney is trailing in second. He also has the potential to do well in the North Dakota and Alaska caucuses.

Mitt Romney

Romney is expected to gather delegates next week in Massachusetts and Vermont, and in Virginia, where only he and Paul qualified for the ballot. He'll win convincingly with the moderate Northeast Republicans of Massachusetts, says Andrew Smith, director of the University of New Hampshire Survey Center.

A recent poll in Virginia, where Santorum and Gingrich — who lives in Virginia — failed to collect enough names to get on the state's primary ballot, showed Romney the pick of 53 percent of those surveyed. If Romney finishes with more than 50 percent of the vote, he'll be awarded a bonus of sorts: 13 statewide delegates, in addition to the ones he picks up in individual congressional districts.

Romney is also considered a favorite in the caucuses in Idaho, where about a quarter of the adult population is, like him, of the Mormon faith.

"But we're looking at who can win outside their comfort zone," Putnam says. Ohio, where Romney is very competitive, appears to be the only state that might fit that criteria and where the former Massachusetts governor has a chance to win.

Newt Gingrich

During an appearance Tuesday on CNN, Gingrich said he "unequivocally" has to win Georgia, which he once represented in the U.S. House. He is seen as the likely victor there, though his once-stratospheric lead in the polls has dropped to the 33 to 39 percent range.

Polls this month showed Santorum overtaking Romney for second in Georgia, but still trailing Gingrich by about 9 percentage points.

A win outside his comfort zone of Georgia? Unlikely, but Gingrich could pull some delegates in Oklahoma. He has lost ground, however, in Tennessee, another state that was part of his Super Tuesday strategy.

Though a pro-Gingrich superPAC reportedly has received another big infusion of cash from casino magnate Sheldon Adelson, Gingrich's path post-Super Tuesday remains increasingly difficult.

Ron Paul

North Dakota is where Paul's opportunity lies, Putnam says. Paul remains a wild card, able to peel off a few delegates from congressional districts and running his delegate strategy in the caucus states.

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