Unfortunately, this seems to be tied to the fact that his daughter isn't doing very well. She was just released from the hospital, but has Trisomy 18, which is a horrible genetic disorder. She's likely to continue to have severe medical issues.
I think that Santorum's campaign, although surprising, has not been good for the GOP. I do give him credit that he's been able to trip up Romney more than anyone thought possible a year ago. But his coalition, such as it is, is not something the Republicans really want on display.