As we move through the halftime break in the Republican nomination process, all of the campaigns have an opportunity to retool their strategies, or even rethink their possibilities.  The New York Times reports that Rick Santorum has tweaked his approach on the stump, moving away from hard attacks on Mitt Romney and focusing more on Barack Obama:

Rick Santorum has eased up on using phrases like “worst Republican in the country” when tearing into Mitt Romney. And he is no longer saying that a vote for Mr. Romney would be basically the same thing as a vote for President Obama.

Meet subdued Santorum.

After several highly publicized remarks that left many in his party questioning whether he had crossed the line in attacking a fellow Republican, Mr. Santorum has struggled to find the balance between being a tenacious underdog and leaving himself open to criticism that he is just an embittered also-ran.

He still reserves plenty of derision for Mr. Romney, mocking him repeatedly as the “Etch A Sketch” candidate whose conservative values are malleable and insincere. But in campaign speeches across Wisconsin the past few days he has directed more of that outrage at Mr. Obama, particularly over the issue of government-mandated health care.

He is now refraining from more pointed language. Mr. Romney is “uniquely disqualified,” as Mr. Santorum has mildly put it, to make the argument for conservatives that Mr. Obama’s health care plan should be repealed.

The opening lead is rather dishonest, and seems to be intended to provide cover for NYT colleague Jeff Zeleny, who got chewed out by Santorum for twisting his words on the stump.  Jeffrey Peters’ link to the source for the quote “worst Republican in the country” goes to the NYT’s Caucus Blog, which actually gets the quote correct, emphasis mine — ironically, a post written by Zeleny:

Rick Santorum urged Republicans here Sunday evening to carefully study the record of Mitt Romney, declaring: “He is the worst Republican in the country to put up against Barack Obama.”

That’s hardly the same thing as calling Romney “the worst Republican in the country,” and Santorum relates it directly to Romney’s health-care reform in Massachusetts in a year when Republicans can expect to attack Obama on ObamaCare.  That’s hardly outside the bounds of debate over the nomination; it’s a concern conservatives have had since the beginning of the nomination process.  That doesn’t mean Romney can’t make the case for himself, and he has — even here on my show as recently as last week — but Santorum’s criticism of Romney’s record is hardly unique within the Republican Party, and hardly the sharpest offered in that vein, either.

Still, critics of Santorum have accused him of being too shrill, especially since it appears that Romney has the only chance of winning the nomination in the primary process.  Recently, Santorum said he’d consider a running-mate slot on the GOP ticket, which means that he’d have to tone down his rhetoric sooner or later anyway.  And if a recent poll in Pennsylvania is accurate, it will have to be sooner rather than later.  Salena Zito interviewed a few political analysts (including myself) about Santorum’s prospects in the race nationally and in Pennsylvania, and what a loss in the Keystone State would mean:

Republican strategist Brad Todd said Santorum faces a tough series of contests before Pennsylvania, especially primaries in Wisconsin, Maryland and Washington, D.C., on Tuesday.

“I think with Wisconsin, it will be hard to stitch a narrative together, even by his most ardent backers, if he loses there to go on,” said Todd, noting polls show Santorum trailing Romney by 8 percentage points in the Badger State. “The support isn’t there for him. Losing another blue-collar, Catholic-rich Midwestern state to Mitt Romney isn’t a good story to tell.” ….

The campaign should end before the April 24 primary here if the former senator continues to slide in opinion polls and lose other primaries, said Ed Morrissey, editor of the widely read conservative blog, Hot Air.

“Losing in Pennsylvania not only finishes him in the race, but it may finish him for good,” said Morrissey, who caucused for Santorum last week in Minnesota.

Of course, it’s worth pointing out that the FMC poll showed Santorum still leading by two points in Pennsylvania, but that was a 13-point drop from the previous month’s poll in the FMC series.  We won’t likely see a Rasmussen, Survey USA, or PPP poll from Pennsylvania until after next week’s primaries, but a further collapse in support there should have Santorum considering whether it would be better for his future prospects to avoid an embarrassing home-state defeat by withdrawing.  Santorum will be 54 years old in May, which would make him 58 in 2016 if Republicans lose this election, and 62 in 2020 if they win.  He has plenty of time to build strength and try again later, but another home-state loss added to the 2006 result might reinforce the notion that Santorum simply can’t sustain a campaign.

Joe Trippi, who ran Howard Dean’s campaign in 2003-4, understands why Santorum may not want to consider those issues:

“It is very hard to pull out of that once you start to taste victory,” Trippi said. “I understand the human difficulty of walking away.”

If Santorum can’t win Pennsylvania, then the nomination race is over anyway.  If it looks like his support is truly collapsing after next week’s primaries, it might be time for rethinking rather than retooling.  If Santorum can win in Wisconsin, though, Pennsylvania will suddenly look a lot brighter.