There is little doubt that Social Security will be a main topic tonight. As I noted earlier, Texas Gov. Rick Perry sounded less extreme on the subject in his USA Today op-ed, but he really didn’t take anything back.

Tim Miller, a spokesman for Jon Huntsman, tells me: “Govs. Perry and Romney are both on record in their books calling Social Security a Ponzi scheme and a fraud, not much that can be done to walk those quotes back.” Miller adds: “Though I guess that hasn’t stopped Gov. Romney before.” (In case you had any doubt that Huntsman’s animosity toward Romney is often not far beneath the surface.)

But the Mitt Romney camp claims that Perry, Huntsman and Perry-friendly pundits are barking up the wrong tree. A Romney adviser tells me that “the issue he takes with Gov. Perry’s stance is not the funding, it is the fact the Gov. Perry has advocated for Social Security to be abolished as a federal entitlement program.” Well, what have Romney and Perry actually said?

The Romney adviser is right that in the last debate Perry was attacked for suggesting Social Security wasn’t worth preserving. Romney said in response to Perry’s remarks:

You can’t say that to tens of millions of Americans who live on Social Security and those who have lived on it. The governor says look, states ought to be able to opt out of Social Security. Our nominee has to be someone who isn`t committed to abolishing Social Security, but who is committed to saving Social Security. We have always had, at the heart of our party, a recognition that we want to care for those in need, and our seniors have the need of Social Security. I will make sure that we keep the program and we make it financially secure. We save Social Security. And under no circumstances would I ever say by any measure it’s a failure. It is working for millions of Americans, and I’ll keep it working for millions of Americans. And we’ve got to do that as a party.

Romney is referring to a series of remarks by Perry. In Perry’s book Fed Up! and through a Perry spokesman’s e-mails to me, the idea of devolving Social Security back to the states has been suggested. Likewise, he’s argued in his book that Social Security is a “failure.” His book also argues that “at the expense of respect for the Constitution and limited government” we have operated under the current Social Security system. That almost, but doesn’t actually, assert that it is unconstitutional.

It’s fair to say at this stage that Huntsman, Romney and Perry all consider the current system to be unsustainable in its current form. Romney has strongly defended keeping the system at the federal level and reforming it. Perry has used incendiary rhetoric, which opponents claim make him an easy target in the general election, but he now seems to be waffling on whether it really is a “failure” and whether sending it to the states is such a good idea.

One interesting note: Huntsman’s spokesman says of his candidate, “He has already expressed support for the Ryan plan and offered support for a variety of reforms to Social Security, including means testing, gradually increasing the retirement age, and giving more options for younger workers.” That’s better than the others have done, but which of those plans does Huntsman prefer? Maybe we will find out tonight.

In any event, it appears that Perry is trying to walk the fine line between damage control and defiance. He’s not a guy who wants to concede a point, and not to Mitt Romney of all people. But if he can pull back his remarks without casting doubt on his true convictions, maybe he also can avoid the other minefields in his book (repealing the 16th and 17th amendments, letting states legalize pot, allowing states to decide gay marriage). If he can pull some about-faces, he could put to bed some of the doubts about his electability. He had better hope that in doing so the Tea Party doesn’t perceive him as just another squish.