Romney continues to lead his foes in the delegate hunt, adding at least three dozen to his total after beating Rick Santorum in Michigan and Arizona.
But with 437 delegates on the table next Tuesday, and with most of them allocated according to each candidate's share of the vote, all four of the GOP contenders are certain to boost their delegate counts, giving everyone in the field a rationale, however thin, to move forward.
The Super Tuesday map features both bright spots and traps for every candidate -- Romney is expected to coast to easy wins in Massachusetts and Virginia, for instance, but faces a tough slog in states like Ohio and Tennessee -- meaning that no one is likely to emerge as an outright victor when the smoke clears.
With none of the candidates boasting an across-the-board advantage, a handful of contested states will take on outsized importance.
The day's biggest prize is Ohio.
Though the state has 10 fewer delegates than Georgia, Ohio carries enormous symbolic weight both as a general election bellwether and a Republican proving ground.
Ohio will test each candidate's ability to connect with GOP voters of all stripes -- from rural, small town conservatives to working class whites to wealthier moderates in the suburbs around Cincinnati and Cleveland.
Romney trailed Santorum by double digits in Ohio prior to his win Tuesday night in neighboring Michigan, a state where Santorum had hoped his blue-collar pitch would resonate.
Santorum came up short in Michigan and Romney emerged with a much-needed win after a month that highlighted his vulnerabilities as a candidate, but Ohio Republicans say Romney's path forward is still fraught with challenges.
(...) "Romney is suffering from the same soft feelings among Republicans in Ohio as he is everywhere else," said one high-ranking GOP figure in Ohio who is not supporting any candidate in the race. "And don't forget, a big swath of this state is basically right next to western Pennsylvania, where Santorum's wheelhouse was."
(...) The stakes are unquestionably highest for Gingrich, who has pinned his hopes on Super Tuesday ever since his deflating loss to Romney in Florida in January.
Since then, Santorum has seized the conservative, anti-Romney mantle while Gingrich has limped through February, longing to compete in several southern states where his campaign hopes his Georgia roots and bold conservative rhetoric will hold appeal.
On Sunday, Gingrich said a win in Georgia is "central to the future of our campaign," a tacit admission that anything less than a win in his home state would derail his sputtering candidacy.
Ralph Reed, a GOP strategist and a former chairman of the Georgia Republican Party, said Gingrich must be considered the frontrunner there because of his longstanding goodwill with party veterans and his endorsements from Gov. Nathan Deal and members of the state's Congressional delegation.
(...) Along with Georgia, the Gingrich campaign is hoping to snare delegates in Ohio (66), Tennessee (58), Oklahoma (43) and parts of Idaho (32), where delegates are awarded on a county-by-county basis.
Though his candidacy is in far better shape than Gingrich's, the coming week will also present several key tests for Romney.
He is all-but-certain to win his home state of Massachusetts (41) and Virginia (49), where only he and Paul managed to qualify for the ballot.
Romney is also expected to perform well in Idaho, where Mormon voters, who backed the former Massachusetts governor by wide margins in previous contests, could exceed 30% of the caucus vote, according to some Republicans in the state.
But primaries in Oklahoma, Tennessee and Georgia may once again call attention to Romney's frosty relationship with hardline conservatives.
(...) Romney's drubbing in South Carolina earlier this year raised questions about his ability to win over conservatives in the South -- the GOP's most reliable voting bloc in general elections -- if he eventually wins the nomination.
His performance in the southern states on Tuesday could either squelch some of those concerns or exacerbate them.
"Romney has to show some kind of lift in the South, and not just in Virginia," said Republican pollster Ed Goeas. "Ohio is going to be the big battle that day, but I would also look to see what happens in Tennessee and Georgia."
Republicans agree that Super Tuesday will not determine the party's nominee, but it could very well harden the emerging outlines of the Republican race.