Cr edit:  Indeed, how does that saying go? Abstinence makes the heart grow fonder, I think?

(CBS News)

By Chip Reid

Polls show Rick Santorum surging ahead of Mitt Romney in Michigan, where Romney grew up, in the race for the Republican presidential nomination.

Both candidates campaigned there on Thursday, taking shots at each other.

It wasn't long ago that the campaign trail was a lonely place for Santorum.

Now, his events are packed, and he's become the darling of evangelical Christians and Tea Party supporters. His popularity is due in large part to his deeply conservative views on social issues.

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But now, he's going straight at Romney on the economy, saying, "(Former Massachusetts) Governor Romney supported the bailout of Wall Street and decided not to support the bailout of Detroit."

Santorum worked to protect his new front-runner status by attacking Romney.

Clearly feeling the heat, Romney hit back, criticizing Santorum for decisions he made as a U.S. senator (from Pennsylvania), saying, "Rick Santorum voted five times to raise the debt ceiling. ... He also voted and continued to defend earmarks. ... During Rick Santorum's term in office, the government in Washington grew by 80 percent. Eighty percent!"

Santorum's poll numbers have soared in recent weeks. And now, Romney's trailing him in Michigan, Romney's home turf, where Romney was born and raised and where his father was governor.

Some political analysts say Santorum's surge is not really about him, it's about Romney. "They're looking for somebody, anybody but Romney," says Larry Sabato of the University of Virginia. "They've seized on everybody from Rick Perry to Herman Cain to Newt Gingrich and now, finally, Rick Santorum."

But many establishment Republicans fear that, if Santorum wins the nomination, past controversial statements -- on contraception, for example -- won't play well in the general election.

On Thursday, Foster Friess, who's contributed hundreds of thousands of dollars to the Super PAC that supports Santorum, ignited a firestorm of criticism when he attempted humor in calling for abstinence. "You know," he said on "Andrea Mitchell Reports" on MSNBC, "back in my days, they used Bayer aspirin for contraception. The gals put it between their knees, and it wasn't that costly."

"Excuse me, I'm just trying to catch my breath from that," Mitchell replied.

Liberal women's groups reacted with outrage to Friess' comment, calling it insulting and irresponsible and demanding that both Friess and Santorum apologize.

Until now, President Obama's campaign had been focused like a laser beam on Romney, but there are now reports that they're starting to focus some attention on Santorum.

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