WASHINGTON (Reuters) - Republican presidential hopeful Rick Santorum's hard-charging focus on social issues has created a quandary for rival Mitt Romney, who usually prefers to steer clear of such sensitive topics and stress his business credentials.
By warning of "the dangers of contraception," claiming that some pre-natal tests should not be covered by insurers because the tests encourage abortions and accusing Democratic President Barack Obama of following "phony theology," Santorum has staked his candidacy on appeals to the social conservatives who are especially influential in Republican nominations.
The new focus by Santorum - who has moved slightly ahead of Romney in national polls - has at least temporarily shoved aside Romney's efforts to keep the narrative of the race focused on the economy.
Instead, with a debate for the four remaining Republican candidates scheduled for Wednesday night in Mesa, Arizona, and the Michigan and Arizona primaries looming on February 28, the state-by-state Republican race has become enmeshed in topics such as birth control, pre-natal testing and even the influence of Satan.
Romney, who has struggled to find an effective line of attack on Santorum, cannot criticize the former Pennsylvania senator as out of step on such issues without antagonizing conservatives who already distrust Romney for his past shifts on abortion and healthcare, analysts said.
Romney's campaign "can't attack (Santorum) from the right because it's not credible and they can't attack him from the left because it raises questions about Romney's conservatism," Republican strategist Matt Mackowiak said.
Romney, a former Massachusetts governor, so far has largely ignored Santorum's turn to social issues, sticking to his economic script and casting himself as a principled conservative with hands-on experience in economic issues as the former head of a private equity firm.
His attacks on Santorum have focused on Santorum's record of backing expensive projects as a member of Congress, and on Santorum's long record as a "Washington insider."
Side-stepping Santorum's comments on social issues could be the best approach for Romney, strategists said.
Santorum's comments could hurt him with women and moderate Republicans, as well as those who are worried about his ultimate electability if he were to win the nomination and the right to face Obama in the November 6 election.
"This was a very self-limiting approach by Santorum," Republican strategist Rich Galen said, adding Romney was never going to win the party's most conservative voters during the primary. "By bringing these issues to the fore, Santorum has reminded everyone else why they don't want him to be the nominee."
Wednesday's debate, which also will include former U.S. House of Representative Speaker Newt Gingrich and Texas congressman Ron Paul, will be the first time in nearly four weeks that the Republican contenders will face off in a debate.
The debate, on CNN at 8 p.m. EST, will give Santorum his first national stage since he swept Romney in three contests in Colorado, Michigan and Missouri on February 7 and charged to the top of the Republican pack.
It also gives Santorum a chance to expound on his comments on Obama's "phony theology" that was "not based on the Bible," his warnings about birth control, and his allegation that Obama's healthcare overhaul encouraged abortion by requiring insurers to cover various prenatal tests used to identify abnormalities.
Santorum has since said the remark about theology was not meant to question whether Obama was a Christian but instead the president's allegiance to "radical environmentalists" who believe in climate change "that elevates the Earth above man."
Santorum's various comments on religion and social issues have spawned a wave of reports about his past musings on such subjects.
This week, a video surfaced of a Santorum speech in Florida in 2008 in which he declared that "Satan has his sights set on the United States of America" and was attacking U.S. institutions.
"With Santorum, like with most individuals, his strength is also his weakness," Mackowiak said. "His strength is that he is a true believer.
"But the downside is, if you never make a political calculation, sometimes you make mistakes and sometimes you say things that go too far and that the broad middle (of the electorate) won't really accept," Mackowiak added. "Santorum is going to have to get a little more disciplined."
The shift in the debate toward social issues followed the political firestorm raised by the Obama administration's rules requiring schools, hospitals and other religious institutions to provide birth control to employees, which drew the anger of officials of the Catholic Church.
Obama eventually adjusted the rule to make insurance companies and not the institutions themselves responsible for insurance coverage, but that did not stop the criticism from Catholic bishops and from Santorum, a staunch opponent of abortion and gay rights who has seven children.
Santorum is the latest in a string of Republican candidates who have risen to the top of the pack as conservatives in the party have sought an alternative to Romney.
Polls show next week's contests in Michigan and Arizona are close. A week after those primaries, on March 6, 10 states will have contests on "Super Tuesday" in a burst that could finally give the Republican race a clear front-runner.
"If this is the approach Santorum is going to take through Super Tuesday, he's going to find that is a strategic error," Galen said. "There are a significant portion of Republican voters who are not in the same camp with him. I'm not sure why he decided to go back to that."
Editing by David Lindsey and Eric Walsh