Republicans in knife-edge race
Phoenix - Struggling Republican hopeful Mitt Romney faces a crucial TV debate on Wednesday as he fights to regain his White House pole position after a surge by Christian conservative Rick Santorum.
Romney's future hangs in the balance, as in a week's time he could either be restored as the frontrunner in the Republican presidential race or be left staring into a political abyss.
Former Pennsylvania senator Santorum, who fiercely opposes gay marriage and abortion, has surged from a distant third into first place following his trio of wins earlier this month in the state-by-state contest.
But up for grabs on February 28 are Michigan, where Romney was born and his father was governor, and Arizona, another supposed Romney stronghold where a significant proportion of the electorate shares his Mormon faith.
Both states were considered shoo-ins for Romney until a short time ago, but such has been the extent of Santorum's popular surge that the rising star now leads in Michigan and is within striking distance in Arizona.
A Santorum win in either would be a huge blow to Romney going into "Super Tuesday" on March 6, when 10 states vote simultaneously in a potentially decisive night for the battle to see who will take on President Barack Obama in the November general election.
Too close to call
A Quinnipiac University poll out on Wednesday found Santorum leading Romney 35% to 26% among nationwide Republicans, followed by former House speaker Newt Gingrich at 14 and Texas congressman Ron Paul at 11.
But the poll found that Obama would defeat Santorum in a general election while an Obama-Romney face-off would be too close to call, adding fuel to Republican concerns about Santorum's electability.
"This week is very important," Peter Brown, assistant director of the Quinnipiac University Polling Institute, said as Romney geared up for the crucial debate on Wednesday, followed by a major speech in Detroit on Friday.
"If he were to lose Michigan, the story will be [that] he can't even win the state where he was born and grew up and where his father was governor. On the other hand, if he wins Michigan, he is the comeback kid."
On the eve of the CNN-run debate in Arizona, Santorum - whose trio of February 7 victories in Minnesota, Missouri and Colorado catapulted him into the lead - sought to rally voters at an afternoon event in Phoenix.
"We are not just here to debate, we are here to win Arizona," Santorum said to a crowd of sign-waving supporters on Tuesday.
Romney, employing the same tactic he used to good effect in Iowa and Florida to see off strong challenges from Gingrich, has launched a barrage of vitriolic attack ads against his chief opponent.
His ad campaign appears to have had some success in Michigan as the latest polling data showed the protagonists virtually tied. Santorum had surged to a double-digit lead there last week.
But a new CNN/TIME survey in Arizona showed Santorum slashing Romney's own double-digit lead there to just four percentage points, within the margin of error.
Campaigning on Tuesday in Shelby Township, a suburb of Detroit, Romney rattled off his usual message that only he has the business acumen to turn around a US economy he said was suffering from Obama's failed policies.
But after hearing him wax lyrical about growing up in Michigan, the crowd of about 500 people were more interested in quizzing him about social issues such as abortion - which Santorum wants to keep at the heart of the campaign.
Initially "pro-choice", Romney switched to a "pro-life" stance after being elected governor of liberal Massachusetts, declaring that the debate over stem cell research had convinced him of the "sanctity of life".
The one-time proponent of gay equality has morphed into an opponent of gay rights as a presidential candidate, signing a pledge to support a federal constitutional amendment defining marriage as between one man and one woman.
On Tuesday, Romney assured the crowd that he was 100% pro-life and fought legislation that would have allowed same-sex marriages in Massachusetts.
His answers, especially on abortion, were enough to satisfy Feleiteau Epley, aged 58. "It's the most important issue. If they're not that [pro-life], I'm not going to vote for them," she said. "My conscience won't let me."
Santorum - whose social conservatism is seen as rock-solid - faces the question of electability in a general election, where such moralising is likely to turn off many independent voters.